Persistant O2 Sensor Problem
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From: Apex, NC
Persistant O2 Sensor Problem
All - I have a 92 Am Cup Car that has a persistant O2 sensor failure - this causes a Check engine light and a O2 sensor persistant condition. The O2 sensor is only 4K miles old and was replaced at a minor service at that time (no valve adjustment) the check engine light comes on once the car is warm and not exceeding 4K rpm's but goes off if i rev the engine (in gear) up to 4.5K +
the car only has 20K miles on it, a KN cone air filter, and a cup bypass pipe. other than that is blanced and Blueprinted as per specs.
i just changed the DME relay to a 993 unit.
Any Idea's - could the air filter or exhaust cuase this? (far fetched?) or anything else. i have run some 100 octane fuel through the system but do not run it solely.
the car only has 20K miles on it, a KN cone air filter, and a cup bypass pipe. other than that is blanced and Blueprinted as per specs.
i just changed the DME relay to a 993 unit.
Any Idea's - could the air filter or exhaust cuase this? (far fetched?) or anything else. i have run some 100 octane fuel through the system but do not run it solely.
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If the O2 sensor has been replaced with a good one and you're still having problems, it implies it's not the O2 sensor but the wiring itself between the sensor and the DME...could even be a ground problem somewhere in the path.
Have you tried pulling the codes from the car (by yourself if possible on your car, or by having the car Hammered)?
<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
Have you tried pulling the codes from the car (by yourself if possible on your car, or by having the car Hammered)?
<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
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From: Apex, NC
i was wondering that (if it was a harness issue) but the symptoms are repeatable (i.e. reving the engine over 4K clears the check engine light) i have pulled the codes (w/o a hammer) it is the O2 persistant code
