SCpower

Okay well heres the situation... The car dies while driving or during idle at no matter what rpm the engine is at.

Whats tricky about it, is that the car has good voltage right after it gets jumpstarted and the alternator maintains a healthy 14.6v. But 5 minutes later the voltage drops extremely fast and goes below 9v and i've seen it go as low as 7v before I had to shut the car off.

I have just replaced the alternator about 24 hours ago, cleaned all the grounds, rewired a 4 gauge positive wire from the alternator to the battery about half an hour ago, and the battery is less than 1 year old. Im running out of ideas =[
anyone have any input on a problem like this? Ive seen other people having voltage issues (read up on about 4 of them) and not a single one was solved or fixed. Or at least they never posted the results on the fix.

1siksc

iTrader: (8)

battery, try a buddies if you have too. Happend to my friends dsm.

SCpower

Yeah ill try popping in my cousins optima yellow top to check.. I was just reading another thread and it said that it might be the fuel ecu killing the voltage. It might be the problem but im not sure yet.

But after observing the car more while its on, I found out that the voltage dies right when the car reaches optimum running temperature. I hear something click off and I feel the engine rpm drop, and thats about the same time the voltage soars to the single digits...

Well ill study the problem at school tomorrow (UTI glendale heights!!!) and ill see if theres any TSBs on the issue.

SHOLEXMAN

Make sure that click isn't the a/c compressor or a short of some kind. See if the connector going into the back of the alternator isn't messed up or burned.

mkorsu

Any updates on this SC??? I am currently suffering from the exact some issue. New alternator and still the problem. Checked all wires from alternator to battery and no noticible problems. I am at a loss. I am trying a DENSO alt (most recent was one from a local Thul's auto supply) since I heard from a Toyota mechanic who is also a LS4 owner that sometimes an aftermarker alt just doesn't want to work with the car.

I'll PM you as well.

TheMole

iTrader: (13)

I had the electrical ghosts where the car would almost die if I were to signal or brake. I went with an aftermarket alternator and the problem came back. Then tried an oem one and thought it was fine, but problem came back yet again. Finally, I replaced the negative cable with an oem 1GS cable and haven't had any issues since. It can be something you guys can look into.

SCpower

Lol back to relive my thread... After a long year of not having the SC running I finally went back to the garage to see what I could do....

I found out that the problem was not the alternator at all and was not an electrical fault in any way....

The harmonic balancer pulley was seperated at the rubber piece and U could not tell by looking at it or turning it... There was enough grab that the alternator would charge while idling but as soon as u drive or put a load on it, the pulley slipped.

Johnny3

Had the same problem with an Acura, belt pulley was slipping on the C/S hub.