low voltage
Thread Starter
Joined: Jun 2008
Posts: 618
Likes: 57
From: Houston/Clear Lake, TX.
low voltage I'm new and I need some help. I have a bad low voltage problem. In park and neutral the the car has 12 volts., around 11 volt. in drive, and 10 volt. when its in drive and the a/c is on. If I'm driving it and I come to a stop with the a/c on, the volts. drop even more and the car will die if i don't throw it in neutral. I've checked....
I would like to check this off the list before I up grade all the old wires and/or take the car to someone and have the little red wire on the back of the alternator to the juction box redone , which will cost me. If any body would like to put there two cents in on how to fix this problem I would love to hear it.
- the battery and put two diffrent ones in the car and the volt. didn't chang
- changed the alternater 3 times . Its a 140 amp now and it does charge. Its never killed my optima
- no underdrive pully
- volt. reading at the battery is the same as the gauge in the car
- checked all visible grounds
- and it doesn't have a stereo
I would like to check this off the list before I up grade all the old wires and/or take the car to someone and have the little red wire on the back of the alternator to the juction box redone , which will cost me. If any body would like to put there two cents in on how to fix this problem I would love to hear it. 
Staging Lane
Joined: Jun 2007
Posts: 72
Likes: 0
From: Syracuse, NY
There is a ground on the passanger side engine mount to the block. Another one from the ICM to the fender. One from the Battery to the fender... and... that's it? I forget.
Check the exciter wire from the alt to the pcm, and the battery to alt power wire.
Check the exciter wire from the alt to the pcm, and the battery to alt power wire.
Thread Starter
Joined: Jun 2008
Posts: 618
Likes: 57
From: Houston/Clear Lake, TX.
Oh yea, Its a 1993 Z28 and its a speed density car. Yes, the belt is tight because it was a pain to put it back on when I just got done replaced the alternator, and no there aren't any squeals when the air is on.
usually a toasted regulator will send your charge level through the roof when you are driving though. i know when mine went out it would reach 18v! when you checked your grounds, did you check the actual ground point? paint or rust will definitely create a poor ground issue.
Thread Starter
Joined: Jun 2008
Posts: 618
Likes: 57
From: Houston/Clear Lake, TX.
usually a toasted regulator will send your charge level through the roof when you are driving though. i know when mine went out it would reach 18v! when you checked your grounds, did you check the actual ground point? paint or rust will definitely create a poor ground issue.
