90 grand prix check gauges

Oh yes this is a problem, I understand a common problem with these cars. My 91 GP did the same thing. The technician at the Pontiac dealer told me as long as your gauges are reading normal it is a false reading. I got adventurous one day and tore into the thing...it was driving me crazy! I removed the circuit card from behind the instrument cluster. I work for a military electronics company and was able to inspect it under a microscope. It was full of bad solder joints and probe holes. Probe holes from a technician trying to diagnose problems when it was originally assembled. I went through and touched up all the bad solder joints. It has been perfect ever since!!! A little quality assurance goes a hell of a long way....COME ON GM!!! I realize military and commercial quality specs are very different but this could have been so easily avoided!!

Hope this helps..

Tom

I still love my GM cars!!

That's because you can fix 'em.

BTW I had a sony CD changer that acted up, after a couple of nights I found a transistor that was soldered on in the wrong position!! (but it worked nice for a few years). Fixed that, but then the changer didn't work at all, kept working on it, found a bad relay, changed it and it works perfect. Most circuits have problems, most are so poorly designed that it doesn't matter or show.