1993 Chevy Cavalier Codes

ABLEE

MEMBER
1993 CHEVROLET CAVALIER
4 CYL
FWD
AUTOMATIC
14,000 MILES

I have a 1993 Cavalier. The problem is only when the car shifts down under acceleration. At the time it shifts down, it starts to bog out and will not recover unless you let off. Otherwise, it runs ok. I scanned and got two codes. 21 and 23. One says, MAT is too low and the other says throttle body sensor is too high. My question is this. Can these items be adjusted, or is replacement required to correct the components performance on the car? Thanks for any help you can provide.

1 Reply

WILDFIREV9

MEMBER
49 POSTS

The tps (throttle positioning sensor) and the mat (manifold air temp sensor) are not adjustable.
Check connectors before replacing.
The mat you may be able to CAREFULLY clean it but I would replace it if the wiring isn't the problem.
The tps is not adjustable or cleanable. It tells the pcm how far open (or not) the throtle plate is so the pcm knows how much fuel to send as well as timing adjustments.
While you're at it, take out the idle air bypass valve and carefully clean the carbon and krud from it.
After you're done, disconnect the battery for at least 30 seconds to clear the codes.
Actually, should disconnect the battery first.
If all this doesn't fix it, have the cat checked for clogging.
Hope this helps, if so, a vote of confidence would be nice.

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