This is a problem I've had with this car simce I bought it but it seems to be worse now that I installed the FMS pulley kit. The power door locks randomly lock and unlock on their own when the car is running. Also the speedo tends to bounce around between 0 and 20MPH when in gear but sittng still. I had thought it might be a problem with the pos. battery cable as it was a funky looking replacement, but I changed that today and it's still doing it.
Any thoughts? Alternator? Voltage regulator?
It's starting to drive me nuts.
Help?
Well, for the speedo. you gears in the trans/driveshaft area are probably shot, or going to be. I would also check all of you grounds in the car, to make sure the nothing is jumping or shorting out.
Grounds. My headlights would come on and of over bumps. Fix the ground no more worries.
I might believe that if it were acting funny all the time, but it's only when it's stopped, and tonight I saw it jump with the trans in park. I suspect it's electrical and as I said both problems got worse AFTER I installed the pulley kit.
i dont have the funky speedometer thing. but i got the same cursed door locks. my car has an alarm system in it, i thought i disabled it(cus its been fine for a year or two) but these last couple months, somehting happened. i see a little red light underneath my dash now(one thats never come on before) and my doors will lock and unlock. i just grew to ignore it now, but i'd look for any alarm systems installed aftermarket
I have an alarm installed and I haven't completely ruled it out yet. But the alarm doesn't explain the problem getting (both of them) geting worse after the pulley install.
If it happened before the pulley install, the pulley install likely isn't the problem ;) It becoming worse may be coincidence, or the lower system voltage might be amplifying the problem.
It could also be (and in fact most likely is) two completely unrelated problems. I've heard of the IVR (instrument voltage regulator) causing some wonky gauge behavior. Could be chaffed wires under the car, could be a bad connection at the speed sensor, could be a bad connection at the cluster (if the printed circuit is corroding)...
The locks are likely caused by the alarm...
It's probably very unrelated, but my '92 SHO, when I had it, exhibited the strangest bunch of behaviors when the alternator wasn't charging properly. Airbag light once you go over 20 mph, door locks working intermittently, ATC codes at random. Very strange things.