Need some help guys. I'm trying to diagnose a friend of mine's 2001 Chevy Impala with the 3.4L V6, She started off by having a dead battery. It was dead because the alternator was only producing 8V. Knowing that those Chevy alternators have the voltage regulators built in them I figured the alternator was just worn out considering the milage (200,000). I did notice the alternator had been replaced before, but not recently. I replaced with a reman alternator from Napa, and after installing I tested and had once again 8V coming from the alternator. I unplugged all the connections, checked for any corrosion or split wires and found nothing. I re-installed the alternator once more and the second time around I got a good charge being produced (14V). So as of then I gave the car back to her considering maybe I just had a loose connection at first install and her problem was fixed. I got a call the next day from her saying her car was down again. I had to jump start her car once more and once again I'm only getting 8V out of the alternator. Ive checked all the fusable links associated with the charging system, PCM, and ECM. All are good and so are all the connections from the alternator, to the starter, and to the battery. All with low resistance on all cables. I'm kinda stumped on this. The only thing I can think is it was a faulty reman alternator since it warranteed I got and need to swap it out once more, but I dont want to go through 10 different alternators and that not even be the problem. You guys got any ideas you wanna throw out there to help?
Monday, November 19th, 2012 AT 4:44 AM