Puppet_Master

My alternator went out on me a few days ago, so I went to autozone to buy a new one. They didn't check it before I left and within 15 minutes of driving it was dead. I figured I was sold a bad alternator, so I went back to buy another one and this time they checked it worked before I bought it. With that one the alternator jumped up to 18v for a while (20 minutes of driving) and then failed completely. So I went back to autozone and brought in my yellow top battery since it didn't seem that it was holding a charge that well. After my alternator would die, the battery would only run my car (with all accessories off) for about 15 miles. They ran some test on the battery and said it was good, so I just replaced the alternator again and made sure there was a solid connection with the regulator inside the alternator.

The alternator ran fine since the last replacement (about 65 miles) and now my alternator is acting up again by shooting up to 18v and varies with RPM. This seems like a regulator problem but since the regulator is new with each alternator I get, I don't think that's the problem.

Could it possibly be the computer? What else could it be?

Thanks,
Andy

Marc 85Z28

iTrader: (8)

With a cheap aftermarket alternator, the regulator is usually reused. If you're lucky, you'll get a very poorly built Chinese piece. Like most things aftermarket (alternator, starter, AC compressor, etc) it may take 3-4 units before you find one that works.

If you insist on aftermarket rebuilt crap, at least stop by a real parts store like a NAPA or O'Reillys.

WS6Power

test it with a volt meter. your gauge my be going bad.

NonGoggleGuy

Yeah, like WS6Power said, check it with a meter. You could also unplug the regulator plug and see if your gauge goes to 0.

Otherwise, it has to be the regulator.

Puppet_Master

I checked the voltage and, sure enough, it's at 18v with the car on. The alternator carries a life time warranty; So I guess I'll try a new one. If this happens much longer, I'll probably buy a new regulator to go on the rebuilt alternator.

So is the consensus that it's most likely the poor quality regulator on the rebuilt alternators that is causing the issue?