94 Bonneville - Car not charging adequately while on
I've had a problem where the voltmeter in my car is showing the battery charge to be anywhere from 8.5 V - just over 14 V. It is reading accurately. The car has only actually stalled once, but it has required a jump many times.
I have had the alternator tested (and it was just replaced last July) and it passed all 3 tests Autozone ran. The battery was replaced at the same point in July. The grounds appear to be in good connection and clean.
The needle bounces up and down, it is not just a constant drain. It'* as if sometimes the alternator charge is not getting back to the battery to charge it, but then it kicks through briefly enough to keep the car running. There will be times where the needle will stay relatively at the same point and bounce up and down slightly, as if there is a short or a bad piece of hardware draining the power and the alternator can't keep up with it.
There were some wires that were damaged by the drive belt. I cut off the damaged sections and replaced them with some other wiring. The repair was pretty decent, I'm not going to claim it was perfect. It did make the charge more stable (less bouncing), but it is still not where it used to be at just above 14 V and stable. The wiring connections are strong, electrical taped, and the heat coiling around the outside was replaced.
The ICM does get VERY hot, especially on the bottom. I had it tested about 6 months ago and it passed the test, but it could have gone bad since then. It stays hot for a very long time after the car is off also (hours).
The car seems to run decent on my way to work most times at 8 am. I'm not sure if this is because it'* the first time running it that day or because it'* cooler outside. We have had 90 degree weather consistently. It doesn't run perfect on the way, but it was steady this morning at probably 13-13.5 V most of the half hour trip, but it went down to just around 12 V as I arrived. When I turned it back on for lunch 4 hours later, it held steady right around 12 V and dropped a little bit under.
The only non-factory accessories in the car are a stereo (head unit only) and a remote starter. I pulled the fuses on the remote starter to ensure no power was going to it, and it did not make a difference. All of the wiring is still connected to it, but no power is going through from the battery anyway.
Last edited by kparrent; 06-03-2010 at 02:32 PM.