650 - 650NK - Techinical Service Manual.pdf - Mojo Motorcycles

FUEL SYSTEM (EFI) 3-23
Symptoms or Possible Causes
Actions (chapter)
Spark weak:
Battery voltage low Inspect and charge (see chapter 16).
Spark plug dirty, broken or gap maladjusted Replace (see chapter 2).
Stick coil trouble Inspect the stick coil (see chapter 16).
Stick coil shorted or not in good contact Reinstall or inspect stick coil (see chapter 16).
Spark plug incorrect Replace it with the correct plug (see chapter 16).
IC igniter in ECU trouble Inspect (see chapter 16).
Crankshaft position sensor trouble Inspect (see chapter 16).
Stick coil trouble Inspect (see chapter 16).
Fuel/air mixture incorrect:
Little fuel in tank
Supply fuel (see Owner’s Manual).
Air cleaner clogged, poorly sealed, or missing
Clean element or inspect sealing (see chapter
2, 3).
Air cleaner duct loose Reinstall (see chapter 3).
Air cleaner O-ring damaged Replace (see chapter 3).
Fuel tank air vent obstructed Inspect and repair (see chapter 3).
Throttle body assy loose Reinstall (see chapter 3).
Throttle body assy O-ring damage Replace (see chapter 3).
Fuel fi lter or pump screen clogged Inspect and replace fuel pump (see chapter 3).
Fuel pressure regulator clogged
Inspect fuel pressure and replace fuel pump (see
chapter 3).
Fuel line clogged Inspect and repair (see chapter 3).
Inlet air pressure sensor trouble Inspect (see chapter 3).
Inlet air temperature sensor trouble Inspect (see chapter 3).
Thermostat trouble Inspect and replace (see chapter 4).
Unstable (rough) idling:
Fuel injector trouble Inspect (see chapter 3).
Main throttle sensor trouble Inspect (see chapter 3).
Crankshaft position sensor trouble Inspect (see chapter 3).
Throttle valves not synchronizing Inspect (see chapter 2).
Inlet air temperature sensor trouble Inspect (see chapter 3).
Coolant temperature sensor trouble Inspect (see chapter 3).
Fuel pressure too low or too high Inspect (see chapter 3).
Battery voltage low Inspect and charge (see chapter 16).
Incorrect idle speed:
Coolant temperature sensor trouble Inspect (see chapter 3)
Main throttle sensor trouble Inspect (see chapter 3).