Code 45 - Rich Exhaust Indication
Code 45 indicates that the ECM has seen:
- High oxygen sensor voltage.
- More than specified time (about 2 minutes).
- Above a specified TPS value.
- Closed loop.
A high voltage can be caused by a rich exhaust or an oxygen sensor contaminated with silicone.
NOTE:
The following step numbers refer to the numbers in the accompanying flow chart(s).
- Dwell under 50° indicates that engine should be checked for cause of intermittent rich condition; purge or bowl vent valves leaking, fuel in crankcase, fuel in evaporative canister, or sticking mixture control solenoid metering rods.
- This step tests ECM response to a lean engine condition. A drop in dwell indicates that ECM and oxygen sensor are not faulty.
- This step tests ECM response to a lean oxygen sensor signal (low voltage). If no dwell change with a grounded lead to oxygen sensor term. "9," fault is in ECM. Open oxygen sensor wire would have set Code 13.
- This step checks voltage from the ECM at the oxygen sensor harness. Normal voltage at this point is the ECM bias voltage for no oxygen sensor signal, approximately .45 volt. If voltage is high, the wire to the ECM could be shorted to battery voltage, or ECM is faulty.