TECHNICAL NOTES ON THE EEC-IV MCU - Auto diagnostics

ECT
Pulse Width
(mS)
150 2.35546875
180 2.04687500
65534 2.04687500
Table 47: Cranking Fuel Pulse width vs. ECT
Eectch98-Part2.fm
The Cranking Fuel Pulse width vs. ECT Function parameters are stored beginning at
787A as 16-bit words. The “X” values (ECT) are signed and must be multiplied by 2 to
convert them to decimal. The “Y” values (pulse width in milliseconds) are unsigned
and must be divided by 256.
Battery Injector
Voltage Offset
0 7.50000
5.5000 7.50000
6.0000 5.53125
7.0000 5.53125
8.0000 2.59375
9.0000 2.03125
10.0000 1.68750
11.0000 1.40625
12.0000 1.15625
13.0000 1.00000
14.0000 0.90625
15.9375 0.90625
Table 48: Injector Offset vs. Battery Voltage
The Injector Offset vs. Battery Voltage Function parameters reside at 7B30 as
unsigned, single byte values. The “X” values (Battery Voltage) have to be divided by
16 to convert them to decimal and the “Y” values (Injector Offset) by 32.
Open Loop Fuel
RPM
Multiplier
0 1
0 1
0 1
1075.00 1
1100.00 0
16383.75 0
Table 49: Open Loop Fuel Multiplier vs. RPM
The Open Loop Fuel Multiplier vs. RPM Function parameters live at 7DE8 as unsigned,
16-bit words. Divide the “X” values (RPM) by 4 to convert them to decimal and the
“Y” values (Open Loop Fuel Multiplier) by 128.
Dashpot[lb/min] Decrement Rate [lb/min]
0 0.003417968750
0.0620117187500 0.002929687500
0.3500976562500 0.001953125000
0.4499511718750 0.007080078125
0.6499023437500 0.044921875000
0.7500000000000 0.062500000000
EEC-IV Technical Notes: Software 37 last edited: 9/29/98