BMW 118d Diesel Start Stop Technology - Transports Canada

BMW 118d Diesel 

Start Stop Technology 

Test Results Report 

June 2011 

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ecoTECHNOLOGY for Vehicles 1

Disclaimer notice 

Transport Canada's ecoTECHNOLOGY for Vehicles program ("eTV") tests emerging vehicle technologies to 

assess their performance in accordance with established Canadian motor vehicle standards. The test results 

presented herein do not, in themselves, represent an official determination by Transport Canada regarding fuel 

consumption or compliance with safety and emission standards of any motor vehicle or motor vehicle 

component. Transport Canada does not certify, approve or endorse any motor vehicle product. Technologies 

selected for evaluation, and test results, are not intended to convey policy or recommendations on behalf of 

Transport Canada or the Government of Canada. 

Transport Canada and more generally the Government of Canada make no representation or warranty of any 

kind, either express or implied, as to the technologies selected for testing and evaluation by eTV, nor as to their 

fitness for any particular use. Transport Canada and more generally the Government of Canada do not assume 

nor accept any liability arising from any use of the information and applications contained or provided on or 

through these test results. Transport Canada and more generally the Government of Canada do not assume nor 

accept any liability arising from any use of third party sourced content. 

Any comments concerning its content should be directed to: 

Transport Canada 

Environmental Initiatives (AHEC) 

ecoTECHNOLOGY for Vehicles (eTV) Program 

330 Sparks Street 

Place de Ville, Tower C 

Ottawa, Ontario 

K1A 0N5 

E-mail: eTV@tc.gc.ca 

© Her Majesty in Right of Canada, as represented by the Minister of Transport, 2009-2011 

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Table of Contents 

EXECUTIVE SUMMARY .............................................................................................. 4 

1.0 INTRODUCTION.................................................................................................. 5 

2.0 TESTING PROGRAM .......................................................................................... 6 

3.0 TESTING LOCATIONS ....................................................................................... 6 

4.0 VEHICLE OVERVIEW ....................................................................................... 7 

5.0 PHASE I - LABORATORY TESTING ............................................................... 8 

5.1 2-CYCLE VS. 5-CYCLE FUEL CONSUMPTION CALCULATIONS ................................. 10 

5.1.1 2-Cycle Fuel Consumption Results ............................................................. 12 

5.1.2 Corporate Average Fuel Consumption (CAFC)......................................... 13 

5.1.3 5-Cycle Fuel Consumption Results ............................................................. 14 

5.1.4 New York City Cycle Fuel Consumption Results ........................................ 16 

5.1.5 Japanese 10-15 Mode Fuel Consumption Results ...................................... 17 

5.1.6 Emissions Results ........................................................................................ 17 

6.0 PHASE II – DYNAMIC TESTING.................................................................... 20 

6.1 ACCELERATION EVALUATION ............................................................................. 21 

6.2 MAXIMUM SPEED IN GEAR .................................................................................. 22 

6.3 HANDLING ........................................................................................................... 24 

6.3.1 Lateral Skid Pad ......................................................................................... 24 

6.3.2 Emergency Lane Change Manoeuvre ......................................................... 25 

6.3.3 Slalom ......................................................................................................... 27 

6.3.4 Turning Circle ............................................................................................. 27 

6.4 NOISE EMISSIONS TESTS ..................................................................................... 28 

6.5 BRAKING ............................................................................................................. 30 

6.6 SUMMARY REMARKS REGARDING DYNAMIC TESTING ......................................... 31 

7.0 PHASE III - ON-ROAD EVALUATIONS ........................................................ 31 

8.0 CONCLUSIONS .................................................................................................. 33 

9.0 WHAT DOES THIS MEAN FOR CANADIANS? ........................................... 33 

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EXECUTIVE SUMMARY 

Diesel vehicles are typically 20-30% more fuel efficient than comparable gasolinepowered 

vehicles. In the past, the advantages of diesel-powered light duty vehicles were 

overshadowed by operational deficiencies compared to gasoline vehicles such as noise, 

vibration, harshness (NVH), higher emissions of oxides of nitrogen (NO x ) and particulate 

matter (PM) in the exhaust, and poor cold starting performance. Due to advancements in 

the diesel combustion process and exhaust treatment, the positives of this technology may 

now outweigh the negatives for consumers who are searching to reduce their fuel 

consumption and carbon footprint. Modern clean diesels can be a clean and cost effective 

alternative to traditional gasoline-powered vehicles. 

The ecoTECHNOLOGY for Vehicles (eTV) program acquired the BMW 118d because it 

possesses a number of advanced technology features that reduce emissions and help save 

fuel. The BMW 118d is one of the most fuel efficient vehicles in BMW’s European line 

up, and is equipped with start-stop technology. 

Criteria 

Fuel consumption 

CO 2 emissions 

Exhaust Emissions 

Start-Stop 

Performance Results 

Driver Evaluations 

Results 

In 2-cycle testing, with the start-stop system turned ON, the fuel 

consumption values were 5.89 L/100 km for the city, 4.73 L/100 km for 

the highway and 5.30 L/100 km for combined city/highway. 

Testing cycle Without With % savings 

start-stop start-stop 

2-cycle (City) 6.04 5.89 2.5 

Adjusted 

5-cycle (City) 7.02 6.94 1.5 

NYCC 9.87 8.61 12.8 

Japanese 10-15 5.98 5.38 10.1 

Real World 4.95 4.60 7.0 

In combined city and highway testing, with the start-stop system 

turned ON, the BMW 118d obtained an unadjusted value of 

124.7 g/km, which is 10% lower emissions than the current best 

performer in the Canadian compact class and a 21% improvement over 

all models within its class. 

Start-Stop has the ability to reduce emissions due to the vehicle’s 

engine not operating at vehicle stops. However, carbon monoxide 

(CO) emissions did rise on restarts, possibly due to a catalyst cooling at 

engine stops. 

In all testing cycles, the use of start-stop offers considerable fuel 

consumption savings in simulated city driving conditions. 

The start-stop experience proved positive with most evaluators. The 

major concern identified was the lack of availability of the technology 

in cars available for sale in Canada today. 

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Barriers to the Introduction of Start-Stop Technologies into the Canadian Market 

Public opinion research has generally established that fuel consumption and vehicle 

emissions have not traditionally been of primary importance to the Canadian consumer 

when shopping for a new vehicle 1 . One of the principal barriers to the introduction of 

advanced vehicle technologies, such as start-stop, is overcoming the consumer’s desire to 

minimize the initial purchase price (or ‘sticker shock’) of a new vehicle, often at the 

expense of longer-term operating costs and environmental impacts. Conversely, 

innovative technologies that improve fuel efficiency often increase the initial purchase 

price of a vehicle. When confronted with the choice of paying more for advanced vehicle 

technologies such as stop-start, consumers often opt for a lower initial purchase price, 

unaware of the potential savings that the technology might offer. 

In addition, fuel consumption test procedures and vehicle ratings can under-estimate the 

potential real-world benefits of start-stop technologies, particularly in city driving 

conditions. To help better assess the potential real world benefits of start-stop 

technology, eTV tested the BMW 118d on the standard 2-cycle and 5-cycle duty cycles, 

and also on the urban-centred New York City Cycle (NYCC) driving cycle and the Japan 

10-15 mode driving cycle. The start-stop system demonstrated significantly greater 

potential fuel savings over the urban centred cycles. 

Testing also supported the development of codes and standards, which need to keep pace 

with innovative new vehicle technologies, in order to ensure the safety and efficiency of 

the Canadian transportation system. 

The testing that eTV has undertaken in relation to start-stop technologies, for example, is 

essential in helping to engage industry and stakeholders in leading-edge research to 

support the development of new or modified codes and standards for all technologies, 

including advanced clean diesel technologies. 

1.0 INTRODUCTION 

The BMW 118d was acquired by Transport Canada’s ecoTECHNOLOGY for Vehicles 

(eTV) program in March 2010 to conduct testing on the vehicle’s start-stop system. In 

addition, benefits of the vehicle’s clean diesel engine and emissions were also tested. 

Historically, diesel vehicles have not been a significant portion of the Canadian light duty 

fleet. Additionally, newly introduced emissions regulations in 2006 enforced a reduction 

in the amount of oxides of nitrogen (NO X ) a new vehicle was allowed to emit. The 

introduction of more stringent regulations temporarily reduced the availability of lightduty 

diesel vehicle models in the 2007 model year as manufacturers developed new 

models and emissions treatments systems. Today, however, there are several 

manufacturers now offering diesels across their product line in Canada. Technologies 

such as common rail direct injection, exhaust gas recirculation, urea injection combined 

1 Pollution Probe. 2008. Barriers to Consumer Purchasing of More Highly Fuel-Efficient Vehicles: A 

Background Paper. 

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with selective catalytic reduction converter (SCR) catalysts have been developed to 

reduce NO X emissions and particulate matter (PM) to meet required levels. 

The start-stop system is a technology that has been widely introduced in the European 

marketplace by several manufactures across a number of vehicle types. The eTV 

program previously tested the smart fortwo mhd, a gasoline powered vehicle equipped 

with a start-stop system and an automatic transmission. The BMW 118d is equipped 

with a start-stop system, a diesel engine and a manual transmission. Results from 

previous testing have demonstrated the promising fuel savings potential of start-stop, 

particularly in city driving conditions. eTV is using this test vehicle to help further study 

on this technology. 

2.0 TESTING PROGRAM 

The testing program was designed to evaluate the effectiveness of the start-stop system 

installed on the BMW 118d, as well as the vehicle’s fuel consumption and exhaust 

emissions both with the start-stop system turned on and turned off. Laboratory 

evaluations were based on practices used by the U.S. Environmental Protection Agency 

(EPA), the U.S. Department of Transport (DOT), the International Organization for 

Standardization (ISO) and the Society of Automotive Engineers (SAE), (see BMW 118d 

Test Plan for details). 

The BMW 118d was evaluated over three distinct phases: 

Phase I - Laboratory fuel consumption and exhaust emissions testing 

Phase II - Dynamic track testing 

Phase III - On-road evaluations 

Together, these various phases were designed to assess the BMW 118d’s overall 

performance, and identify any possible barriers that could adversely affect the 

introduction of its advanced technologies into the Canadian market. 

3.0 TESTING LOCATIONS 

Phase I testing was performed in partnership with Environment Canada at the Emissions 

Research and Measurement Section (ERMS) located in Ottawa, Ontario. All testing was 

performed in a controlled laboratory, using a vehicle chassis dynamometer. The 

laboratory environment ensures that testing was completed to within ± 1 degree Celsius 

of the required test temperature. Vehicles are tested according to separate driving cycles 

and are maintained to within ± 1.5 km/h of the required speed. 

Phase II testing was performed at Transport Canada’s test track facility in Blainville, 

Quebec. The controlled environment was necessary to ensure that testing was performed 

on a gradient of ± 1%. The test track is equipped with over 25 kilometres of road, 

including both a high-speed and low-speed circuit, to allow for a variety of tests. Phase II 

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testing was performed between July 17 and November 8, 2010. Tests were carried out 

only in weather conditions that were favourable to evaluation and testing standards. 

Phase III vehicle evaluations were performed by Transport Canada staff. 

4.0 VEHICLE OVERVIEW 

The BMW 118d is classified as a compact vehicle according to Canadian standards. It is 

equipped with a 1,995 cc (~2 litre), variable turbine geometry turbocharger, 4-cylinder 

engine. The vehicle is also equipped with other technologies, such as common rail direct 

injection, which can help limit vibration and emissions through precise injection at high 

pressures; and low rolling resistance tires, which help to limit fuel consumption and 

greenhouse gas (GHG) emissions. According to available BMW publications, the 118d 

is described as being capable of achieving 1,133 km range on a 51-L tank of fuel, based 

on a European combined fuel consumption rating of 4.5 L/100 km. The same tests 

indicate that the vehicle produces only 119 g/km of CO 2 . Detailed specifications for the 

vehicle are presented in table 1. 

Table 1: Specifications for the 2010 BMW 118d 

Weight 1,385 kg Drive Type Rear-wheel 

Length 4.24 m Engine Inline 4-cylinder 

turbocharged, common rail 

direct fuel injection with 

start-stop technology 

Width 1.75 m Transmission 6-Speed Manual 

Height 1.42 m Torque 300 Nm / 221 lb-ft @ 1,750 

rpm 

Seating 5 Power 105 kW / 143 hp @ 4,000 

rpm 

Fuel Type Diesel (low sulphur < 

15ppm) 

Manufacturers Stated 

Fuel Consumption 

City 

Highway 

5.1 L/100 km 

3.8 L/100 km 

Displacement 1,995 cm 3 Fuel Tank Capacity 51 L 

Top Speed 194 km/h Driving Range 1,133 km (based on European 

driving cycles) 

Acceleration 0-100 in 12.5 seconds Brakes (f/r) Disc /Disc with ABS 

CO 2 Emissions 119 g/km Drag Coefficient 0.30 

This particular diesel engine/power train model was chosen because of the start-stop 

system installed on a vehicle with a manual transmission. The system is designed to 

detect an impending vehicle stop and shut off the engine at speeds lower than 5 km/h, 

provided the driver has also placed the transmission in neutral and disengaged the clutch 

pedal. The engine control unit (ECU) will detect the vehicle coming to a stop and 

automatically turn the engine off. The engine automatically re-starts when the driver 

engages the clutch pedal. Based on available information, start-stop systems have the 

potential to reduce fuel consumption, particularly in city driving conditions. 

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Figure 1: BMW 118d Clean Diesel Test Vehicle 

The user can turn the start-stop system ON or OFF by depressing a button located on the 

vehicle’s dash near the transmission shifter. When the system is switched OFF, the 

vehicle will idle at all stops. If the driver chooses the ON position, however, the startstop 

system will engage when the vehicle is at idle and shut off the engine. A picture of 

the start-stop system activated on the vehicle dash is shown in Figure 2. 

Figure 2: Start-stop system engaged – illuminated while activated 

5.0 PHASE I - LABORATORY TESTING 

More than 3,500 kilometres of vehicle use were accumulated on the BMW 118d, in 

keeping with the Code of Federal Regulations (CFR) mileage accumulation procedure. 

The procedure outlines the prescribed route that the vehicle must follow, using 

commercially available diesel fuel with no blended bio-diesel. Once mileage 

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accumulation was completed, the vehicle was soaked 2 at a laboratory temperature for no 

less than eight hours before testing began. This is to ensure that the vehicle’s test 

temperature is controlled for comparison against other test vehicles undergoing the same 

emissions and fuel consumption evaluations. 

Emissions and fuel consumption tests were performed, as per the standard CFR 

procedures and procedures listed by the Japanese legislation for passenger cars (New 

Long Term Standards). Evaluations were performed over the seven duty cycles listed in 

Table 2. Each set of tests was performed with the start-stop system engaged and 

disengaged (denoted as ON and OFF), for comparative analysis. 

A laboratory setting offers highly repeatable results, as environmental conditions can be 

kept constant. As well, a defined driving cycle can be performed to simulate real world 

traffic conditions. In addition all instrumentation was placed outside of the vehicle in a 

stationary setting adding no unnecessary weight to the test vehicle. 

Table 2: Chassis Dynamometer Test Schedule 

Test Parameter Testing Standard Number of Tests 

(Cell Temperature) 

Location 

Urban Driving UDDS 4 (22°C) ERMS (Ottawa, ON) 

Cold Test UDDS 2 (-7°C) ERMS (Ottawa, ON) 

Aggressive Driving US06 (SFTP) 2 (22°C) ERMS (Ottawa, ON) 

Highway Driving HWFET 2 (22°C) ERMS (Ottawa, ON) 

Electrical Load SC03 2 (22°C) ERMS (Ottawa, ON) 

Stop-and-Go Driving NYCC 2 (22°C) ERMS (Ottawa, ON) 

Stop-and-Go Driving Japan 10-15 Mode 2 (22°C) ERMS (Ottawa, ON) 

The vehicle was mounted on a chassis dynamometer where the rear (drive) wheels were 

allowed to roll against a resistance drum. The drum’s resistance was pre-programmed, 

using the vehicle’s road load force parameters. Parameters and coefficients were based 

on a vehicle travelling from a speed of 115 km/h to 15 km/h (71.5 mph to 9.3 mph) 

while coasting. The final result was a model for road load force as a function of speed, 

during operation on a dry, level road, under reference conditions of 20°C (68°F) and 

98.2 kPa (29.0 in-Hg), with no wind or precipitation and with the transmission in neutral. 

ERMS collected and analyzed exhaust emissions for each of the duty cycles listed in 

Table 2. The emissions data were analyzed for: 

carbon monoxide (CO) 

carbon dioxide (CO 2 ) 

total hydrocarbons (TC) 

oxides of nitrogen (NO X ) 

2 To soak a vehicle means to park it in the test chamber with the engine turned off and allow the entire vehicle, including engine, fluids, transmission and 

drive train, to reach the test cell temperature prior to the beginning of a test. 

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particulate matter (PM) 

For diesel emissions results, the exhaust gas measuring devices require hydrocarbons to 

be preheated to 190°C to prevent condensation, which have high boiling points. 

Particulate filters are used to calculate particulate emissions. 

For CO and CO2, non-dispersive infrared analyzers (NDIR) are used to perform their 

calculation. 

For NOx, chemiluminescence detectors (CLD) are used to perform their calculation. NOx 

is generally interpreted as the total of nitric oxide (NO) and nitrogen dioxide (NO 2 ). 

5.1 2-CYCLE VS. 5-CYCLE FUEL CONSUMPTION CALCULATIONS 

Two methods were used to measure the fuel consumption of the BMW 118d: 

 

 

The 2-cycle method, which utilizes simulated drive patterns or ‘cycles’ 

representing city driving and highway driving, is the method used to determine 

fuel consumption values published by Natural Resources Canada in the Fuel 

Consumption Guide, as well as on the EnerGuide Label affixed to all new lightduty 

vehicles. 

The 5-cycle method utilizes cycles that simulate city driving, highway driving, 

aggressive driving style, city driving in cold temperature (at -7 ºC), and driving 

with an electrical load due to air conditioning. This test method is generally 

considered to more accurately reflect real-world driving. The U.S. EPA uses this 

method to determine fuel consumption. 

The test cycles are derived from extensive data on real-world driving conditions, such as 

driving activity, trip length and stopping frequency, among other factors. The Federal 

Test Procedure (FTP), or 2-cycle test method, is composed of two tests – the city test 

(using the U.S. FTP-75 driving cycle) and the highway test (using the U.S. HWFET 

The annual Fuel Consumption Guide is 

just one of several decision-making tools 

produced by the ecoENERGY for Personal 

Vehicles program at NRCan. This program 

provides Canadian motorists with helpful 

tips on buying, driving and maintaining 

their vehicles to reduce fuel consumption 

and GHG emissions that contribute to 

climate change. 

driving cycle). Fuel consumption from these 

test cycles are calculated from the emissions 

generated. The fuel consumption ratings, or 

advertised fuel consumption, as published by 

Natural Resources Canada in the annual Fuel 

Consumption Guide, are generated based on 

fuel consumption values from the laboratory 

testing. They are then adjusted, using 

Canadian factors, to reflect real-world 

driving conditions. Advertised fuel consumption is obtained by adjusting the measured 

fuel consumption upward 10% and 15% respectively for the city and highway cycles to 

account for real-world differences between the way vehicles are driven on the road and 

over the test cycles. Combined city and highway fuel consumption is obtained using a 

ratio of 55% city and 45% highway. 

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The 5-cycle test method takes into consideration additional driving conditions including: 

aggressive driving style, use of air conditioning, and urban driving in cold conditions. 

The U.S. EPA began to implement the additional test cycles, known collectively as the 

Supplemental Federal Test Procedure (SFTP), for fuel consumption in 2006, and started 

publishing fuel consumption results according to the 5-cycle test procedure for model 

year 2008 vehicles. Prior to this, both Canada and the U.S. used both the FTP and SFTP, 

or 5-cycle method, for emissions testing of vehicles only. 

The 5-cycle method includes testing over a wider range of driving patterns and 

temperature conditions than those tested under the 2-cycle method. For example, the 

US06 aggressive driving cycle takes into account aggressive driving. Furthermore, 

drivers often use air conditioning in warm and/or humid conditions. The US SC03 test 

cycle reflects the added fuel needed to operate the air conditioning system. As well, 

given Canada’s climate, a typical vehicle will be driven below 0°C on a fairly regular 

basis. The U.S. FTP-72 cold test cycle, conducted at 20°F (-7°C), is used to reflect the 

effect on fuel consumption when starting and operating an engine at lower temperatures. 

Fuel consumption values derived from either the 2-cycle or 5-cycle method have merit 

when used to compare the fuel consumption of one vehicle to that of another. However, 

comparisons are only valid when the method for obtaining the fuel consumption value is 

consistent. For example, a fuel consumption value derived from the 2-cycle method 

should only be compared to other fuel consumption values derived from the 2-cycle 

method. Because it takes other factors into account that typically increase fuel 

consumption, the 5-cycle method usually yields fuel consumption values that are 

approximately 10% to 20% higher than the advertised 2-cycle fuel consumption value for 

the same make and model. However, accurate forecasting of fuel consumption is difficult 

in practice due to the many unpredictable factors that affect driving efficiency. 

Error! Reference source not found. shows a schematic of the process that is used to 

determine the advertised or ‘label’ fuel consumption values. As figured, the 2-cycle 

method used in Canada measures fuel consumption based on the city and highway drive 

cycles. These results are adjusted upward 10% and 15% respectively to produce the 

advertised fuel consumption values. The 5-cycle method uses the city, highway, 

aggressive (US06), air conditioning (SC03), and cold city drive cycles, all of which are 

used to calculate the advertised city and highway fuel consumption estimates in the U.S. 

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Figure 1: How 2-cycle (Canadian) fuel consumption values & 5-cyle (U.S. EPA) fuel economy values 

are calculated 

5.1.1 2-Cycle Fuel Consumption Results 

The BMW 118d was tested twice against the Urban Dynamometer Driving Schedule 

(UDDS) city cycle and the HWFET highway cycle according to current Canadian 

standards for fuel consumption testing, both with the start-stop system engaged and 

disengaged. The results were averaged for each cycle. 

The results for the fuel consumption of the BMW 118d with the start-stop system ON, 

based on the 2-cycle calculations (adjusted 10% and 15% respectively) are 5.89 L/100km 

for the city, and 4.73 L/100km for the highway. An adjusted combined fuel consumption 

value, using a 55% and 45% weighting for the city and highway respectively, is 

5.30 L/100km. 

With the start-stop system OFF, the adjusted 2-cycle calculations were 6.04 L/100km for 

the city. Therefore, driving with the start-stop system engaged in the city returned an 

estimated 2.5 % savings in fuel consumption. It should be noted, however, that higher 

savings are possible. The UDDS city cycle includes 23 stops, but their duration is quite 

short (< 5 seconds) in most cases. Therefore, the system’s full fuel savings are not 

entirely reflected through this particular cycle. The resulting combined fuel consumption 

value, adjusted using a 55% and 45% weighting for the city and highway respectively, 

becomes 5.38 L/100 km. It should be noted that in both cases, the results share the same 

highway results, as the system ON or OFF offers no savings on the HWFET cycle. 

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Table 3: Adjusted 2-Cycle Fuel Consumption Values 

2- Cycle Fuel Consumption Adjusted (L/100km) 

Adjusted Values City Highway Combined City Savings 

Start-Stop OFF 6.04 4.73 5.38 2.5% 

Start-Stop ON 5.89 4.73 5.30 

When the results for the BMW 118d are compared to the sales weighted national average 

for all compact cars sold in Canada in 2010, the city fuel consumption reported for the 

same model year is 8.8 L/100 km 3 . The BMW 118d, therefore, offers a 33% 

improvement in fuel consumption in city driving over all models within the compact 

class. As a reference, Volkswagen’s diesel powered Jetta model reported city fuel 

consumption of 6.7 L/100km and a combined fuel consumption of 5.8 L/100km. 

5.1.2 Corporate Average Fuel Consumption (CAFC) 

The Government of Canada, in conjunction with the motor vehicle industry, sets 

CAFC targets annually. The CAFC targets represent the maximum weighted average fuel 

consumption numbers for new light-duty vehicles. There are two annual CAFC targets 

for new light-duty vehicles - one for passenger cars and another for trucks. Historically, 

Canada's CAFC targets have been harmonized 4 with the Corporate Average Fuel 

Economy (CAFE) standards in the U.S. 

Figure 4 shows the unadjusted 5 2-cycle combined fuel consumption value of 

5.35 L/100 km versus the fleet average for model year 2010, as well as the Canadian 

(CAFC) and U.S. (CAFE) standards. From the following graph, it can be seen that the 

BMW 118d is well below the vehicle fleet average; additionally, the BMW 118d is also 

well below the published target values for both Canada and the U.S. Given the 

limitations of 2-cycle testing, the start-stop system demonstrates fuel consumption 

reduction potential. 

In the past, other technologies that were under represented in the current calculation were 

often given a CAFC credit. Methods such as these might entice manufacturers to 

introduce such systems in the near future. One potential option to encourage 

manufacturers to increase the use of start-stop technology would be to provide such a 

credit. 

3 Based information provided by Transport Canada’s Vehicle Fuel Economy Information System (VFEIS) on model year 2010 compact class vehicles, 

city cycle test (UDDS) 

4 In 2011 fuel consumption regulations are regulated by Environment Canada under the Canadian Environmental Protection Act (CEPA) 

5 Fuel consumption standards are compared to unadjusted values in both Canada and the U.S. Adjusted values are used for labelling purposes only. 

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Fuel Consumption Vs. Vehicle Footprint - Corporate Average Fuel Consumption (CAFC) 

Light Duty Vehicles 

12.0 

Fuel Consumption (L/100 km) 

10.0 

8.0 

6.0 

4.0 

2.0 

United States CAFE Goal 

Canada CAFC Goal 

Sales Weighted 2010 Fleet Average 

BMW 118d Target 

BMW 118d Test Vehicle 

0.0 

0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 

Vehicle Footprint (square feet) 

Figure 4: Unadjusted Combined Fuel Consumption for Model Year 2010 

5.1.3 5-Cycle Fuel Consumption Results 

Each of the 5-cycles is divided into “phases” – also referred to as “bags” because each 

phase sample is bagged and analyzed separately, without interruption, during the test. 

The following equations are derived from 40 CFR Parts 86 and 600, to determine both 

the city and highway fuel economy 6 results for a vehicle. 

Where: 

Bag # FE is the fuel economy in US miles per gallon of fuel during the specified bag of the FTP test 

conducted at an ambient temperature of 75ºF or 20ºF 

6 The term “fuel economy” is used here to reflect the fact that 5-cycle testing is a U.S. standard and not the Canadian standard. In Canada, the term “fuel 

consumption” is used. 

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Under the vehicle specific 5-cycle formula, the highway fuel economy value would be 

calculated as follows: 

The fuel consumption of the BMW 118d, based on the 5-cycle calculations above, is 

7.10 L/100 km for the city and 6.22 L/100 km for the highway, with the start-stop system 

ON. When the start-stop system ON values are compared to the start-stop system OFF 

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values for 5-cycle testing, the start-stop system ON achieves a 1.5% fuel reduction in city 

driving. 

Table 4: 5-Cycle Fuel Consumption Values 

5- Cycle Calculated Vehicle Specific Fuel Consumption (L/100km) 

City Highway Combined City Savings 

Start-Stop OFF 7.02 5.08 5.98 1.5% 

Start-Stop ON 6.94 5.08 5.95 

Although these fuel consumption values are higher than those obtained during the 2-cycle 

testing, the 5-cycle testing values can provide a more accurate representation of what a 

driver can expect in terms of real-world fuel consumption. When compared against the 

city and highway values for the 2-cycle calculation, the 5-cycle fuel consumption values 

are 13% and 7% higher for city and highway driving respectively with the start-stop 

system engaged. 

5.1.4 New York City Cycle Fuel Consumption Results 

The NYCC is a standard emissions cycle developed by the U.S. EPA. This cycle is not 

used for emissions or fuel consumption regulations for light-duty vehicles. However, the 

NYCC is often used in hybrid vehicle research, to help determine the effective range of a 

hybrid vehicle. eTV tested the BMW 118d under the NYCC because it offers a better 

understanding of the vehicle’s performance in heavy city stop-and-go traffic, with quick 

accelerations from a start and longer periods of idling. The cycle was run twice with the 

start-stop system ON and twice with it OFF. The results were averaged for each mode. 

Table 5: New York City Cycle Fuel Consumption Values 

NYCC Fuel Consumption (L/100km) 

City 

City Savings 

Start-Stop OFF 9.87 

Start-Stop ON 8.61 

12.8% 

As Table 5 demonstrates, the BMW 118d achieved a 12.8% reduction in fuel in the 

laboratory when tested against the NYCC. Although, the laboratory offers a wellcontrolled 

environment, its simulated real-world heavy city driving yields slightly 

different results than those presented in the previous sections. 

When compared with the NYCC, the standard fuel consumption cycles (both the 

Canadian 2-cycle and the U.S. 5-cycle) report a lower fuel consumption savings potential 

for the start-stop technology. The stops in city and highway cycles are limited in number 

and very short (less than 5 seconds). The NYCC, with longer stop periods that are more 

consistent with real-world driving conditions, demonstrates results that are almost 13% 

better than the current regulated cycles. The eTV program will continue to work with 

stakeholders, including government and industry, on better ways to demonstrate the full 

benefits of the start-stop technology. 

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5.1.5 Japanese 10-15 Mode Fuel Consumption Results 

The Japanese 10-15 (J10-15) mode cycle is currently used in Japan for emissions 

certification and fuel consumption testing of light duty vehicles. The cycle consists of 

both a city and highway cycle, but with significantly longer periods of idling than those 

present in any other compliance cycle, including the NYCC as just reported. 

The BMW 118d was tested against the J10-15 cycle, in addition to the NYCC. Previous 

testing conducted by eTV on a smart mhd (see smart mhd Test Results Report) 

demonstrated a significant savings on the NYCC, due to the length of stops. eTV 

decided to research the fuel consumption savings on a separate cycle like the J10-15 

cycle, which would reflect both gentle acceleration and braking, and longer stops. 

The J10-15 cycle demonstrates both the benefits of a start-stop system, such as the 

system currently installed on the BMW 118d. Through testing, the technology 

demonstrated significant savings of approximately 10%. These savings may be more in 

line with what a user driving in the city would experience, as typically their own stops at 

lights or in traffic will be longer than those represented in the standard fuel consumption 

cycles (Canadian 2-cycle and the U.S. 5-cycle). 

Table 6: Japanese 10-15 mode Fuel Consumption Values 

Japanese 10-15 Mode Fuel Consumption (L/100km) 

City / Highway 



Savings 

10.1% 

5.1.6 Emissions Results 

The result of the city and highway test cycles is a combined CO 2 emissions value of 

124.7 g/km for the BMW 118d. The four best performing comparable diesel compact 

vehicles for the 2010 model year, currently available on the Canadian market, obtained a 

combined average CO 2 emissions value of 138.3 g/km CO 2 . Thus, technologies such as 

those found in the BMW 118d could offer a 10% reduction in CO 2 emissions over the 

current best performers in the compact class. 

When tested to the sales weighted national average for all compact cars available in 

Canada, the CO 2 emissions reported for the same model year are 157.8 g/km 7 . The 

BMW 118d, therefore, offers a 21% improvement in CO 2 emissions over all models 

within its class. 

With regards to non-CO 2 exhaust emissions, the BMW 118d is well below the Canadian 

emission standards against which it was tested. 

7 Based information provided by Transport Canada’s Vehicle Fuel Economy Information System (VFEIS) on model year 2010 compact class vehicles; 

using 2341 grams CO 2 per litre for gasoline and 2732 grams CO 2 per litre for diesel fuel. 

__________________________________________________________________________________ 


Figure 5: Carbon dioxide emissions with start-stop system ON and OFF 

From Figure 5, it can clearly be demonstrated that start-stop technology reduces carbon 

dioxide because the vehicle’s engine is not idling at stops. Using current test cycles, such 

as those used in Canada, demonstrates an emissions savings of 2.9% for the city, when a 

combined fuel consumption savings is calculated, a 1.9% savings is observed. However, 

additional test cycles such as the NYCC and J10-15 mode demonstrate significantly 

greater savings at 12.7% and 10.1% respectively. It is reasonable to expect similar 

emissions savings in the real world based on the latter cycles, particularly in city driving 

conditions. Current test cycles, though suitable for most emissions and fuel consumption 

measurement, do not include long enough stops to allow the full benefits of the 

technology to be realized. Furthermore, because it is reasonable to assume that vehicles 

idle at traffic lights for longer than a few seconds on most city trips, larger savings may 

be observed in real world driving conditions. 

__________________________________________________________________________________ 


Figure 6: Selected gaseous and non-gaseous emissions with start-stop system ON andOFF 

When tested against the UDDS cycle, there was very little difference between the BMW 

118d’s emissions of CO and NO X with the start-stop ON or OFF. However, when 

analyzing the results of the CO emissions on non-standard test cycles, testing results 

record an increase in CO emissions with the start-stop system engaged. It is important to 

note that while there is increased CO emission of approximately 24% and 79% for the 

NYCC and J10-15 mode cycles, the amount of overall CO is still low, when compared to 

regulated limits for the UDDS cycle. The reasoning for this increase is most likely 

attributed to the catalytic converters’ temperature cooling when the engine is turned off at 

stops. Catalysts need to be at specific temperatures to fully aid in the reaction of 

removing hydrocarbons and emissions. In the case where the start-stop system is turned 

OFF, the CO values remain low simply because the catalyst remains at operational 

temperature. 

The system demonstrated a reduction in NO X when engaged. The standard UDDS city 

test cycle demonstrated a reduction of 6.6% while additional cycles such as the NYCC 

and J10-15 mode cycles demonstrated reductions of 6.3% and 15% respectively. Oxides 

of nitrogen are harmful to human health and ever stringent emissions laws are in place to 

help further their reduction in the Canadian vehicle fleet. Technologies such as start-stop 

may assist manufacturers in meeting their future emissions targets. 

Lastly, the program looked at the amount of PM generated over the UDDS cycle only. A 

decrease in PM was expected with start-stop engaged; however, a large increase in PM 

was noted. This noted increase may be due to the fact that the vehicle underwent a diesel 

particulate filter regeneration process during the test. Particulate matter is more prone to 

formation due to low combustion temperatures, which can also be common on engine 

start up. Particulates tend to burn off in the cylinder at high combustion temperatures. In 

either scenario, re-testing the vehicle’s PM emissions will be necessary for clarification. 

__________________________________________________________________________________ 


Table 6: UDDS - Exhaust Emissions vs. Standards grams/mile & (grams/km) 

Mode CO NMHC HCHO NOx CO 2 PM 

BMW 118d Start-Stop OFF 

0.36 

(0.22) 

0.027 

(0.017) 

0.00109 

(0.00067) 

0.30 

(0.19) 

237 

(146) 

0.002 

(0.001) 

BMW 118d Start-Stop ON 

0.32 

(0.19) 

0.034 

(0.021) 

0.00136 

(0.00084) 

0.28 

(0.17) 

230 

(142) 

0.033 

(0.02) 

Standard – Bin 5 

3.4 

(2.1) 

0.075 

(0.043) 

0.015 

(0.009) 

0.05 

(0.03) - 

0.010 

(0.006) 

Euro 5 Emissions 1.61 

(0.99) 

0.109 

(0.067) - 

0.12 

(0.07) - - 

It should be noted that the values for non-methane hydrocarbons were slightly higher in 

repeated tests on the UDDS, with the start-stop system ON. Although still well below the 

limit established both in Canada and in Europe, the engine restarts may be causing this 

slight increase. There may be some small residual time effect within the exhaust sampling 

system that negatively assesses anti-idling systems, but any such effect should be very 

minor to the point of being difficult to quantify. 

6.0 PHASE II – DYNAMIC TESTING 

The BMW 118d underwent dynamic and performance testing from July 17 and 

November 8, 2010. Most aspects of the tests performed were for general dynamic 

assessment purposes and not as a measure of compliance with the Canada Motor Vehicle 

Safety Standards (CMVSS). Concerns about fuel-efficient vehicles are not always 

limited to GHG reduction. The general dynamic testing was performed because the eTV 

program wished to assess how well smaller, more fuel-efficient vehicles function in 

various road situations, with a view to identifying any possible issues. Consumers in 

North America have misconceptions about diesel performance, ex: slow, noisy, 

unreliable. 

As mentioned previously, the dynamic testing was performed at Transports Canada’s 

Motor Vehicle Test Centre in Blainville, Quebec. An aerial view of the test track is 

provided below. 

__________________________________________________________________________________ 


Figure 7: Dynamic Test Track Facility Overview 

6.1 ACCELERATION EVALUATION 

The maximum acceleration was determined by starting the vehicle from a standing start 

and following the procedure set out below. 

1. The vehicle was evaluated by accelerating to the maximum attainable speed in a 

quarter of a mile (402.3 m). 

2. The vehicle was evaluated by accelerating to the maximum attainable speed in a 

kilometre (1000 m). 

To account for variations in wind, the vehicle was driven in both directions on the test 

track, with the results averaged. 

Table 8: Average Speed Results for Specified Distances 

Distance Speed ( km/hr ) 

1/4 mile ( 402.3 m) 125.3 

1,000 m (1 kilometre) 164.2 

The BMW 118d accelerates from 0 to 100 km/h in 12.5 seconds. Figure 8 displays the 

acceleration curve. 

__________________________________________________________________________________ 


Figure 8: Acceleration Curve 0 – 100 km /h 

6.2 MAXIMUM SPEED IN GEAR 

The maximum speed attainable was tested and recorded for each gear. The driver started 

from a standing start for first gear only. The vehicle was accelerated, changing gears 

only when the vehicle engine speed reached its maximum allowable revolutions per 

minute (rpm). The maximum speed and rpm were recorded. Since speed is affected by 

wind, tests were performed in both directions and averaged. Tests took place on August 

5, 2010 and the recorded wind speed was 11 km/h. 

Table 9 lists the maximum speeds obtained in two separate trials in opposite directions 

for each gear. 

__________________________________________________________________________________ 


Table 9: Average Results for Maximum Speed in Each Gear 

Gear selection 

V max (km/h) 

A. Gear selection no 1 9.9 

B. Gear selection no 2 47.7 

C. Gear selection no 3 86.0 

D. Gear selection no 4 127.6 

E. Gear selection no 5 171.0 

F. Gear Selection no 6 194.1 

During testing, the BMW 118d reached an average maximum speed of 194.1 km/h in 

approximately 74 seconds, while operating in 6 th gear. Thus, the BMW 118d has the 

capability of meeting and exceeding all minimum speed requirements on public roads in 

Canada. Additionally, the torque and acceleration performed favourably to typical 

results in the compact class, and previous vehicles tested against in the eTV program. 

Figure 9 presents the maximum speed and speed in each gear in one direction before 

being averaged. 

Figure 9: Maximum Speed in Gears 1 thru 6 

__________________________________________________________________________________ 


6.3 HANDLING 

6.3.1 Lateral Skid Pad 

The lateral skid pad test was used to determine the maximum speed that the BMW 118d 

could achieve in a cornering situation. When a vehicle reaches its cornering limit, it will 

either under-steer or over-steer, losing traction on the curve. When the vehicle has almost 

lost traction, the maximum lateral acceleration is recorded. 

In order to measure vehicle position, speed and lateral acceleration, the BMW 118d was 

equipped with a combined GPS and accelerometer-based data acquisition system. All 

measurements refer to the vehicle’s centre of gravity. 

Tires were warmed up and conditioned by using a sinusoidal steering pattern at a 

frequency of 1 Hz, a peak steering-wheel angle amplitude corresponding to a peak lateral 

acceleration of 0.5–0.6 g, and a speed of 56 km/h. The vehicle was driven through the 

course four times, performing 10 cycles of sinusoidal steering during each pass. 

Testing was performed under the following conditions: 

 

 

 

 

 

The vehicle was equipped with new tires. 

Tire pressure was adjusted to conform to the manufacturer’s recommendations. 

The vehicle’s weight included one driver, and test instrumentation. 

The skid pad was 61 m in diameter. 

The manoeuvre was performed in both clockwise and counter clockwise 

directions. 

Figure 10: Test Vehicle on a Clockwise (CW) Run 

The results presented in Table 10 show that the maximum speed that the vehicle can 

achieve in a cornering situation is 60 km/h. Entrance speeds above 60 km/h engaged the 

electronic stability control (ESC) system, which immediately reduced the vehicle’s speed 

to 60 km/h. 

__________________________________________________________________________________ 


Table 10: Skid Pad Test Results 

Clockwise 

Counter-Clockwise 

Speed (km/h) Stay Inside Corridor? (Yes/No) Speed (km/h) Stay Inside Corridor? (Yes/No) 

50 Yes 50 Yes 

55 Yes 55 Yes 

60 Yes 60 Yes 

*ESC system is activated, reducing speed to 58 km/h 

Even when the cruise control is engaged, the maximum speed that the vehicle can 

achieve in a cornering situation, with the ESC system turned on, is still 58 km/h. In this 

case, the maximum lateral acceleration obtained while maintaining the skid pad course is 

6.3 m/s 2 (0.64 G’s), based on a peak friction coefficient of 0.98. The coefficient value is 

dependent on several factors that make it almost impossible to predict the friction forces 

(magnitude and direction between tires and the test surface). This complex phenomenon 

depends on a tire longitudinal/lateral motion and will not be discussed here. 

Because the ESC system engaged, the vehicle never reached its cornering limit and never 

lost traction. It can therefore be concluded that the ESC system on the BMW 118d is 

effective in helping to maintain vehicle stability in a cornering situation and, by 

extension, in most road situations. 

6.3.2 Emergency Lane Change Manoeuvre 

The emergency lane change manoeuvre with obstacle avoidance test was performed, 

based on ISO 3888-2: 2002 Passenger Cars – Test Track for a severe lane change 

manoeuvre. During this test, the vehicle entered the course at a particular speed and the 

throttle was released. The driver then attempted to negotiate the course without striking 

the pylons. The test speed was progressively increased until instability occurred or the 

course could not be negotiated. 

Figure 11: Emergency Lane Change Course 

__________________________________________________________________________________ 


As illustrated in Figure 11, section 4 of the course was shorter than section 2 by one 

meter in order to achieve maximum lateral acceleration in this area. Tests were performed 

in one direction only. If any pylons were hit, the run was disallowed. 

Figure 12: Emergency Lane Change Manoeuvre 

The ESC system performed well as it limited the speed of the vehicle to 58 km/h during 

the manoeuvre. The maximum lateral acceleration obtained during this test was 1.08 G’s. 

While there is no pass or fail in terms of speed for emergency lane change manoeuvres, it 

is a fair assessment of the lateral stability of a vehicle. The maximum successful entry 

speed through the course was recorded as 70 km/h. 

Figure 13: Lateral Accelerations Recorded During Emergency Lane Change Manoeuvre 

__________________________________________________________________________________ 


As seen in Figure 13 above, the maximum lateral acceleration recorded on a successful 

run was 10.6 m/s 2 (1.08 G’s). 

6.3.3 Slalom 

The BMW 118d was tested against a typical slalom course which has become a baseline 

test to evaluate the transient response for the vehicle. Transient response is the vehicle’s 

ability to recover from one corner and set up for the next corner. The vehicle’s mass 

distribution can directly influence the position of the centre of rotation for the vehicle, 

which can be either positive or negative in its results against this test. 

There is no set speed limit that is required for a successful slalom test, the driver will 

attempt the course at a set initial speed and progressively increase the speed until the 

course cannot be negotiated. 

Figure 14: BMW 118d Navigating Slalom course at 100 km/h 

The maximum achievable speed for the successful completion of the slalom course was 

100 km/h. When comparing to results on lateral acceleration observed in the emergency 

lane change manoeuvre, peak values are higher during a slalom manoeuvre, at 

approximately 1.12 G’s. 

6.3.4 Turning Circle 

A desirable attribute in any urban environment is the ability to perform simple manouvers 

such as three-point turns, parallel parking, as well as U-turns when applicable. A turning 

circle dictates the path of the vehicle or ability to negotiate a U-turn in a confined space. 

It is the smallest circle that the vehicle is capable of performing. 

For the BMW 118d the vehicle returned an average turning circle of 8.94 meters. For 

comparison, a classic black London taxi has an impressive 8 meter 8 turning circle to 

allow it to perform U-turns in the narrow London streets. For further comparison, a 

typical passenger car is between 11-13 meters. SUV’s turning circles are as much as 15- 

8 Bosch, Robert. Bosch Automotive Handbook, 7 th Ed. Germany: SAE Society of Automotive Engineers, 2007. Print. 

__________________________________________________________________________________ 


17 meters. Therefore, the BMW 118d offers considerable benefits in urban environments 

in terms of slow speed manuouvers. 

6.4 NOISE EMISSIONS TESTS 

The BMW 118d was tested in accordance with the CMVSS 1106 Noise Emissions Test, 

SAE Recommended Practice J986, Sound Level for Passenger Cars and Light Trucks, 

and SAE Standard J1470, Measurement of Noise Emitted by Accelerating Highway 

Vehicles. In order to measure noise emitted from the engine and exhaust, microphones 

were set up as shown in Figure 15 below. 

Figure 15: CMVSS 1106 Noise Emissions Setup 

Testing was performed under the following conditions: 

 

 

The vehicle test weight, including driver and instrumentation, did not exceed the 

vehicle’s curb weight by more than 125 kg; 

For a period of one minute, the vehicle’s engine speed was returned to idle and the 

vehicle’s transmission was set in neutral gear before each run, in order to stabilize the 

initial transmission and exhaust system temperatures. 

The test procedure for the acceleration tests was as follows: 

 

 

 

When the vehicle approached a speed of 48 km/h ± 1.2 km/h, the approaching speed 

was stabilized before the acceleration point; 

At the acceleration point (± 1.5 m), as rapidly as it was possible to establish, the 

throttle was opened wide; 

Acceleration continued until the entire vehicle had exited the test zone; 

__________________________________________________________________________________ 


The sound meter was set to fast dB(A) 15 m from the vehicle. 

The deceleration tests followed the same procedure as above, with one modification – at 

the deceleration point, the vehicle was returned to its idle position until it was equal to 

one half of the approaching speed or until the entire vehicle had exited the test zone. 

Figure 16: CMVSS 1106 Microphone Noise Emissions Setup 

Results from all tests show that the noise levels are within the limits of the CMVSS 1106 

standards. Due to the logarithmic nature of the decibel scale, a level of 

69.3 dB is significantly lower than the 93.8 decibel limit. 

The levels measured for the BMW 118d are typical for a diesel powered vehicle. Most of 

the noise being generated from the vehicle at these test speeds is due to tire and wind 

resistance, which is acceptable and similar across any vehicle power train platform. 

__________________________________________________________________________________ 


External 

Noise – 

Accelerating 

External 

Noise - 

Decelerating 

Approaching 

Speed 

(km/h) 

Table 12: External Noise Measurements dB(A) 

Approaching 

RPM max 

RPM 

(1) 

End Speed 

(1) 

(km/h) 

Noise Level 

dB (A) 

Noise Level 

dB (A) 

Electric 

Vehicle 

48 2750 70 4500 69.3 60.0 

70 4000 62 2000 70.3 60.6 

Interior noise emitted from the vehicle was evaluated at different constant speeds in order 

to determine the levels experienced by the driver of the vehicle. It is interesting to note 

that, when compared to a 100% battery electric vehicle that the program has previously 

tested, the interior noise levels were comparable. When compared directly in Table 13 

for the same test and distance, the diesel engine is only 2 to 5 dB louder than compared to 

an all electric battery vehicle. This truly is strong evidence to support the claim that 

newer diesels equipped with technologies such as common rail direct injection, that limit 

engine vibration and combustion noise, can offer significant reductions in noise 

emissions. Again, much like the exterior noise volumes recorded, the levels are mostly 

attributed to tire and wind resistance against the vehicle as speeds increase. 

Table 13: Internal Noise as observed by microphone placed near driver’s ear 

Noise Level 

Vehicle Speed 

dB (A) 

BMW 118d 

Noise Level 

dB (A) 

Electric 

Vehicle 

Ambient Noise Level 38.1 Engine Off 45.8 

Idle 50.5 Neutral 31.4 

Full Acceleration 75.1 0-100 km/h 70.6 

Average 75.1 110 km/h 70.6 

Average 71.7 100 km/h 70.9 

Average 69.4 80 km/h 67.8 

Average 65.8 50 km/h 61.8 

6.5 BRAKING 

Testing was performed in accordance with the procedures set out in CMVSS 135 - Light 

Vehicle Brake Systems. The BMW 118d is compliant with all aspects of the CMVSS 

135 standard. Figure 17 below displays a sample of the stopping distances at two 

compliance speeds. The performance of the BMW 118d at both speeds is above standard. 

It should be noted that it is typical for all vehicles to exceed the high-speed braking 

standard by a greater relative amount than the low-speed braking standard. This is 

partially due to the difficulty in applying maximum braking pressure at the start of the 

brake test. 

__________________________________________________________________________________ 


Figure 17: BMW 118d Braking Performance 

6.6 SUMMARY REMARKS REGARDING DYNAMIC TESTING 

Overall, the dynamic test results show that the BMW 118d meets the relevant Canadian 

standards. All aspects of its handling and performance were either good, pass or 

acceptable relative to the compact class, and its dynamic performance was similar to that 

of market competitors in its class. In addition, the vehicle met all aspects of CMVSS 

noise and braking standards tested against. 

Regarding noise emissions, when compared to a battery electric vehicle performing the 

same tests, the noise levels were only slightly higher. This can be attributed to an 

improvement in diesel engine technology, such as common-rail direct injection, which 

helps eliminate engine noise and vibration. 

7.0 PHASE III - ON-ROAD EVALUATIONS 

The eTV engineering team and Transport Canada staff evaluated the BMW 118d on the 

streets of Ottawa, Ontario. Drivers were asked to fill in a two-page questionnaire. The 

questionnaire asked evaluators how they perceived the start-stop system before and after 

their experience. In addition, they were asked how the system operated, if it was easy to 

use, if they noticed fuel savings, and noise reductions at stops. As well, the drivers were 

asked to provide comments on the general performance of the vehicle. 

Evaluators reported that they were comfortable with the start-stop system, even in heavy 

city traffic. Users who had previously tested the system on other test programs such as 

the smart mhd, were unaware the system was available in combination with a manual 

transmission. Responses on having to place the transmission in neutral with the clutch 

pedal released to engage the system was forgetful at times. Evaluators commented that 

the system would be improved if it could recognize the stop as well as allow the clutch 

pedal to remain pressed with only the transmission in neutral to save on engine restart 

time. 

__________________________________________________________________________________ 


Much like a previous trial of start-stop systems, evaluators wondered if turning off an 

engine not equipped with a start-stop system could offer the same savings. While similar 

savings might be obtained by turning off the engine in a regular vehicle, it is not really 

designed for multiple restarts and could damage the engine. Additionally, the long term 

reliability of the system, battery and engine due to multiple restarts was also a question. 

The BMW 118d battery and starter/generator, on the other hand, is specifically designed 

to handle multiple restarts. As well, the ECU monitors the state of the battery. When too 

many restarts occur in a short period and/or the accessory load demands on the battery 

approach its cut-off voltage, the BMW 118d will remain in start-stop mode but shifts to 

standby as it recharges the battery, thus preventing any chance that the engine will shut 

off and not be able to perform a successful restart. 

In regards to on road fuel consumption after fuel consumption and emissions testing, 

evaluations in the spring of 2011 provided an opportunity to compare the fuel 

consumption for the start-stop system turned ON and OFF using Transport Canada’s 

mileage accumulation route. The route is a pre-determined path through the city that 

includes approximately 60 km of city driving and 28 km of highway driving. In the case 

of the BMW 118d, the start-stop system was engaged ON and OFF for 1,500 km each, 

with the results recorded using a data acquisition system. 

Beginning with a full tank of fuel, the driver repeated the route until 1,500 km had been 

accumulated in each scenario. At each fuel fill-up, the mileage and the amount of fuel 

were recorded. Table 14 displays the results for the on road testing. 

Table 14: Real-world Fuel Consumption Results 

Real-World Fuel Consumption (L/100km) 

Total Consumption 



City Savings 

7.0 % 

From the results, it is evident a fuel consumption savings of approximately 7.0% was 

recorded based on 3,000 km of on road testing. 

Assuming an average Canadian accumulates 16,249 km 9 per year using a light duty 

vehicle, with approximately 68% city driving and 32% highway driving conditions, as 

demonstrated in our real world testing, the following fuel savings can be approximated to 

be $56.00 10 . However, assuming the system only functions for 6 months of the calendar 

year, as the system does not operate below + 3°C, the fuel savings may actually be lower. 

Overall, numerous factors will determine individual fuel savings, but not limited to the 

following: 

1. Ambient temperature 

2. Percentage of city driving 

3. Frequency of stops 

9 Based on Statistics Canada - Canadian Vehicle Survey for 2009 Light Duty Vehicles 

10 Diesel Fuel at $1.00/Litre 

__________________________________________________________________________________ 


4. Annual mileage 

5. Fuel cost 

8.0 CONCLUSIONS 

The eTV program selected the BMW 118d for testing and evaluation largely because of 

its start-stop system and clean diesel power train. The testing program was designed to 

assess the vehicle’s start-stop technology as well as the diesel engine’s fuel consumption, 

exhaust emissions, and overall handling. 

Results demonstrated the use of start-stop offers savings in fuel consumption in city 

driving, ranging from a 2.5% savings in 2-cycle testing through to a savings of 12.8% 

with the NYCC. In real world on road testing, a fuel consumption savings of 7.0% was 

recorded. 

Reduced fuel consumption with the start-stop technology consequently results in 

significant reduction in CO 2 emissions. As CO 2 emissions are a direct by-product of 

combustion in an internal combustion engine, emissions are expected to decrease 

significantly in an urban environment when stops are frequent. In fact, with the start-stop 

system engaged, the BMW 118d obtained a CO 2 emissions value of 138 g/km, which is 

10% less than the current best performers in the compact class and a 21% improvement 

over all models within the compact class. With regards to non-CO 2 exhaust emissions, 

specifically CO, the use of a start-stop system appeared to cause a significant increase in 

CO emissions, upwards of 24 to 79%. This increase may be due to the catalytic converter 

cooling down at periods of engine stops. For the catalyst to aid in a chemical reaction 

such as reducing CO emissions, it is necessary for the catalyst to remain at an optimum 

temperature. Additional testing will be underway to monitor the temperature of the 

catalyst on all program test vehicles equipped with the start-stop system to better inform 

on this cause and effect. 

The eTV program investigated whether start-stop technologies had an impact on 

performance. During cold-cell testing, the eTV program found that the BMW 118d was 

able to operate above +3C, with varying uses of the auxiliary systems. However, below 

+3C, by design, the vehicle did not allow the start-stop system to engage and turn off the 

engine when idling, despite acceptable battery voltage levels. As the temperature drops, 

the chemical reactions in a battery take place more slowly. The starting power even of a 

fully charged battery, therefore, decreases as the temperature drops. Thus, in Canada, 

some of the system’s fuel saving potential will be lost during cold winter months. 

9.0 WHAT DOES THIS MEAN FOR CANADIANS? 

The data obtained through driver evaluations and testing in relation to a BMW 118d with 

and without start-stop technology activated confirms that significant fuel reductions can 

be obtained when using the start-stop system. The data is consistent and correlates well 

with the fuel consumption testing results for city driving cycles, such as traffic, time 

stopped at lights, varying speeds, wind and weather. 

__________________________________________________________________________________ 


However, public opinion research has generally established that fuel consumption and 

vehicle emissions have not traditionally been of primary importance to the Canadian 

consumer when shopping for a new vehicle. One of the principal barriers to the 

introduction of advanced clean diesel technologies, such as the start-stop system, is 

overcoming the consumer’s desire to minimize the initial purchase price or higher capital 

acquisition cost often at the expense of longer-term operating costs and environmental 

impacts. Conversely, according to a recent study by the National Academy of Sciences, 11 

innovative technologies that improve fuel efficiency often increase the initial purchase 

price of a vehicle. In the case of start-stop technology, it could increase the purchase 

price by upwards of $1,000. When confronted with the choice of paying more for 

advanced vehicle technologies such as start-stop, consumers often opt for a lower initial 

purchase price, unaware of the potential savings that the technology might offer due to 

the fuel consumption listed on the vehicle’s fuel consumption label. 

In addition, fuel consumption test procedures and vehicle ratings may not accommodate 

many of the advanced technologies and, as such, may under-estimate their potential realworld 

benefits. The results outlined in this report support that point, since the 2-cycle 

tests under-represented the fuel savings obtained both in the NYCC, J10-15 mode, as 

well as in real-world city driving conditions. In these situations, not only does the 

vehicle cost more, but also there would appear to be little improvement in the vehicle’s 

published 2-cycle based fuel consumption ratings if it were sold in Canada – a situation 

that compounds existing consumer barriers. eTV continues working with manufactures 

to help introduce start-stop technology in the Canadian vehicle fleet. 

11 National Academy of Sciences. 2010. Assessment of Technologies for Improving Light-Duty Vehicle Fuel Economy. 

__________________________________________________________________________________

BMW 118d Diesel Start Stop Technology - Transports Canada

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