Brand

General Motors

Model

350cui VIN K

Year

1988-1990

13

Oxygen sensor voltage stays between 0.35 and 0.55 volts for 60 seconds

14

Coolant temperature sensor signal indicates a temperature of over 275° F for 2 seconds

15

Coolant temperature sensor signal indicates a temperature colder than -27° F for 30 seconds after the engine has been running for at least 30 seconds

21

TPS voltage was above 2.5 volts for 8 seconds when the MAP sensor signal showed manifold vacuum to be 15 pounds or more

22

TPS voltage was under 0.2 volts for 2 seconds when the engine was running

23

Inlet air temperature sensor signal showed an air temperature below -22° F after the engine has been running for 5 minutes

24

Vehicle Speed Sensor (VSS) Circuit

25

Inlet air temperature sensor signal showed an air temperature over 302° F after the engine has been running for 5 minutes

32

EGR open command did not change MAP sensor signal. Normal EGR flow should cause slight decrease in manifold vacuum which would change MAP sensor signal

33

MAP sensor signal voltage was too high (low vacuum) for 5 seconds when throttle opening was under 4%

34

MAP sensor signal voltage was too low (high vacuum) when engine speed was under 1200 RPM or the engine speed was over 1200 RPM with a throttle position angle above 21%

35

Idle Air Control (IAC) System

42

The EST signal did not change when the ECM applied bypass voltage to the ignition module

43

The ECM did not detect a knock signal during near wide open throttle operation with coolant temperature above 194° F or the knock signal was present for 5 seconds or more during normal engine operation. Electronic Spark Control (ESC) Circuit

44

Oxygen sensor voltage was under 0.2 volts for 50 seconds of closed loop operation (Lean Exhaust Indicated)

45

Oxygen sensor voltage was over 0.7 volts for 30 seconds of closed loop operation with a throttle angle between 2% and 20% (Rich Exhaust Indicated)

51

PROM error. (MEM-CAL)

52

CALPAK error. Fuel CALPAK Missing

53

System Over Voltage

54

Fuel pump voltage was not present at fuel pump sense line for 2 seconds after the ECM has sent the fuel pump on command (Low Voltage)

55

ECM error. Replace ECM. Faulty ECM