More Info on 91 Caprice Classic Problem

[keamom99]

Hi, First off thanks to those of you who replied to my post "help with 91 caprice classic problem" I appreciate all of your suggestions. Here is some more info. Took back to the exhaust place to have them remove catalytic converter to see if problem was in exhaust or engine. It seems to be an engine problem. It is as if there is too much fuel getting into the exhaust. The spark plugs have been changed twice, all of them were black and sooty. We are going to leave it at a friend's house to have him work on it when he has time. This was a detective's car so I know they supposedly upgrade the timing belt. Our friend thought changing the timing slightly might help. We'll see.

[burnM]

Does the check engine light come on?
If it does, there is a simple way to check your codes with a jumper wire. If your car has a OBD1 system, (12 point connection uder the dash) and your check engine light is operational, push one end of a jumper wire into the 'test' terminal, and push the other end into the 'ground' terminal. Make sure to do this with the key in the run position, but with the engine not running.

The light should flash a code 12 which indicates the system is working properly. This means 1 flash, followed by a short pause, and then 2 flashes.(code twelve) After a longer pause, the code will repeat itself 2 more times. If no other codes have been stored, code 12 will repeat itself until you disconnect the jumper wire. If other trouble codes have been stored, they will follow the code 12. Again, each trouble code will repeat itself 3 times before moving on to the next stored code.

If there are any codes stored, count the flashes in the same way as the code 12(1 flash, a pause, and then 2 more flashes) and put them up here, and I'll tell you what my manual says they are.

Does the car idle rough, or lope while idling? Does it surge while driving at speed? Did you check resistance in the plug wires? Or for rubbed out spots on them?

Just trying to get a better idea of the problem.....let us know what happens.