Mechanics

CHEVY BERRETTA

1990 Chevrolet Beretta

Engine Performance problem
1990 Chevy Beretta 6 cyl Two Wheel Drive Automatic 260 th miles

Re: 1990 Chevy Berretta 3.1 liter

Possible clues:

Oil pressure light on dash flashes with key turned on to alt. (Other idiot light just light up, they don’t flash like the oil pressure light.)

Throws a code 21 which has to do with an elevated TPS voltage relative to the air flow.

Single wire from alternator to positive on battery does not have continuity= probable bad fusable link.
I wired sinle wire directly to the positive on battery. Now alternator charges about 14.5 amps but car won’t rev up.(This is the original problem)
In other words when the alternator is not hooked up the car revs up and runs better.

Any ideas the car won’t rev up and run right?
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Acethemechanicnot
February 9, 2010.




From what you describe, you proabl have the alternator wird incorrectly and if you have a bad fusible link repair it and it should solve your problem. YOur tps is either bad or sticking, maybe telling your computer that it's at wide open throttle. If your oil pressur light is flickering at idle it's either a bad oil filter or your main bearings are worn causing this. Bet a good oil filter like a purolator/ac/or wix.
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Hmac300
Feb 9, 2010.
I found a wire that I missed connecting to the starter that fixed my (new)alternator to positive pole on battery contiuity problem. Also, I put a new TPS in. However, I still have the original prolem of car not reving up past 3000 rpms unless I disconnect the pos. On the alternator (then it rev's up) The battery reads 14.81 DC volts when running. I examined the ECM and could find no burned spots or obvious problem.

Tiny
Acethemechanicnot
Feb 11, 2010.
The battery reading 14.81 volts when running is a little bit high. All that means is that the alternator is charging. But you still can have a bad battery. You need to charge it up and taek it to an auto parts store where they can put a load test on it. To make sure it's good and not weak. Itcould also be low fuel pressure due to a clogged fuel filter. If not a pro will have to check the codes to see if something else is screwed up like a cam sensor, but it should be scanned first. It could also have jumped time considering the miles on it.

Hmac300
Feb 11, 2010.
Thanks for all of your good ideas. I will get back with you later after I try some of your suggestions.

Updated 3-1-10
Thanks for your help. I ended up replacing one of the fuel injectors and that fixed it.

Tiny
Acethemechanicnot
Feb 11, 2010.

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