Question about 1998 Chevrolet Cavalier

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PCM Troubleshooting Check light on with no code reader power

Check engine light is on, running rough with no power up hill 40MPH Max. Connected code reader to unit with no power up to reader. Attempted to jump at diagnostic port to flash codes on dash with no luck. Power to A, assuming second spot to jump is reference ground to PCM to force codes to dash, but book doesn't give great detail of wiring to trace back to PCM. Any suggestions or which wires to trace to determine if bad PCM or wiring problem.

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You can't jump the connector to get codes on OBD II. (Pre 1996) Try hooking back up you code reader. If it doesn't communicate, check the fuse for the cig lighter. This fuse should also power up the diagnostic plug.

Posted on Mar 09, 2009

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