Code 45: Rich Exhaust Indication: Notes

Sensor acts like an open sensor circuit and produces no voltage when exhaust temperature is less than 600°F (316°C). An open sensor circuit or cold sensor causes "open loop" operation.

Code 45 indicates a rich exhaust and diagnosis should begin with these items: fuel pressure, leaking injector, HEI shielding, canister purge saturation, coolant sensor, MAP sensor, O2 sensor contamination and TPS intermittent output.

1. Test checks to see if O2 sensor is registering a rich condition. Code 45 is set when vehicle is at operating temperature (in "closed loop"), throttle angle is between 3 and 45 percent, O2 sensor signal at ECM is greater than .7 volt for 30 seconds or more and time since engine start is one minute or more.