Where to begin with multiple repairs

LERMA0413

MEMBER
2000 CHEVROLET CAVALIER
4 CYL
FWD
AUTOMATIC
150 MILES

I have a 2000 Chevrolet Cavalier with a 2.4L engine. About 3 years ago, I was in a car accident that accordion-ed the front end. The body was pulled back into place and repaired, but they said they didn't do anything to the interior as it started right up and had no issues. The first time I drove it a long distance, just about every light on the dashboard lit up; at the same time the speedometer, odometer, and temp and gas gauges all flat-lined. The car itself drove just fine while all these things happened. Over the next few months, it started to show signs of a power distribution problem( if 2 windows went down at the same time, they would both go slower than they would 1 at a time, or if I turned on the defrost, my lights would dim). Still the car managed to run with all of these issues. Now, it randomly stalls while I drive, but starts back up, or it seems to have stalled unless I floor the accelerator. I am sure these are unrelated problems, but my question is this: Where should I start with repairs?

1 Reply

CARADIODOC

MECHANIC
33,752 POSTS

Start by charging the battery, then unplug the connector on the side of the generator. If the engine runs better, replace the generator AND the battery. Starting with the 1987 models GM went from the world's second best DC generator to by far the worst pile ever. It is common to go through four to six of them in the life of the vehicle and they are extremely difficult to disassemble to repair, assuming you know what's wrong with it.

What many professionals are finding out is to reduce the number of repeat failures, replace the perfectly good battery at the same time. It will work fine in older vehicles, but as they age they lose their ability to absorb the huge voltage spikes these generators produce. Those spikes can destroy the diodes inside the generator and they interfere with the signals from various engine sensors. Those spikes cause a lot of running problems, and the generator itself will cause intermittent low or no charge which would be why the windows run slowly and the instrument cluster, which is a computer module, gets confused.