Figures...just when winter is coming on. Whenever I'm driving with the blower on, no problem. When I come to stop sign or red light, the voltage goes down and the car seems to bog. Weird huh? The alternator is new as well as a tensioner pulley. Maybe its time for a new blower motor or perhaps the resistor pack is going out. The problem does'nt occur under the same conditions if I turn the climate controls all the way off. Any thoughts?

Ken

 

Just because the alternator is new doesn't mean it's any good. Either you don't have a good alt or batt, or one of your wires between is no good. The problem is that with the blower on, you're pulling more current than your current alternator can handle, and it's killing your power output. Yes, the blower motor may be overdrawing current, or the resistors may be bad, but I would try a different alternator first just to see, since it shouldn't cost you anything because it is under warranty, right?
There are ppl on here who have gone through 5 or so parts store alternators before they have found a working one, FYI.

 

I would have to agree with Maverick H1L. I had a problem with my 84 dropping voltage when coming to a stop or slowing down and I had to replace the alternator twice to fix the issue. for some reason the first alternator was bad out of the box.

 

i had a new alternator go out 1 week after purchase the bearings went out... best to have them bench tested at the parts store when purchaseing

 

Did you make sure that the pully that is on the new alternator is the same size as the old one. I got 3 in a row that had a smaller pulley than was on my original, which resulted in belt slippage and low voltage at idle.

 

change the pulley from old one to new one = fixed

 

Well....the pully is the same diameter, but they screwed me. The alternator they gave me had a 5 groove pulley instead of a 6 groove. Needless to say. it was tearing my belt all to pieces. I took it back and they put a 6 groove on it.

Ken