Hi,
My 2.8q is dying. The battery failed last week, and would not take a charge or be jump started. After finding a battery (exide, has the vent)and installing it today she started immediately. I drove around for about ten minutes and noticed that my voltage was reading around 15. It has been fluctuating for around two weeks between 13-15. When I came to a red light the car stalled. I started it, and stalled again, start it, then stalls, start, stall. It starts fine, runs fine but stalls when comes to a stop, or I slow down 5-10mph, and now stalls as soon as its started.
I am thinking its the alternator, I am open to all suggestions. By the way its a 99 with 53k miles. I am posting here because it seems the members on this board are more mechanically inclined.
Thanks for any help.
TR
99' A6q
01' 530i
00' ml55
95' 928gts

If your voltage is fluxuating like that I'd suspect the alternator as your problem. As to why its stalling out, I don't think that would be alternator related. That might be a different problem. I'd take it to your nearest Audi dealer and have them run a test on the alternator and pull any codes from the ECU. That will give them an idea of why its stalling. They'll be able to tell if your alternator is bad also. Best of luck.

...the battery on the 30v but is it possible you disconnected any vacuum lines. This could cause this stalling!!

Next....
I would check, with a digital multimeter, what your car is getting for voltage. (I know you have a multimeter since you own a 928 :) Start the car and hold the leads to the battery to see what you get. Ideally, you want it in between 13.8-14.2V. If that checks you can quit suspecting the alternator.

If alternator is okay I would look at your battery cables. Here's some things to look for..

1) Was there any corrosion on the connectors for the cables??
2) Are they connected tight and well seated on the battery?
3) Is there a short on the positive battery cable (break in the insulation somewhere)??
4) Use your multimeter and test the resistance of the ground cable. If it's high, make sure the ground is securly attached to the grounding point. If that looks good it may be a bad ground cable (had that on your 928 yet.....oh wait, I don't think the GTS's had a ground wingnut, did they??). To check the ground cable, check the resistance from the battery directly to the ground point (compare the resistances with the cable and w/o the cable)!!

I would guess it's 3 or 4. Although a bad alternator is also a (remote) possibility!!

Good Luck!!

You sure are right about the electrical gremlins in the 928 :). But, I have another question for you. The road side assistance driver who came to jump my car (THEN TOW), said he had two 2000 amp batteries hooked up to his jumper cables, do you think this might have fried my voltage regulator and or alternator. Do you know if the voltage regulator is internal to the alternator?
Thanks
TR

....was dumb enough to have two batteries that big hooked up you're lucky he didn't fry your car :) To answer your question...I doubt it. You'ld be WAY more likley to fry the sensative components in your computer before you fry your voltage regulator.

In Audi's they are internal. Although on the older Audi models you can replace just the regulator. You may be able to do this on the 30v too...but again, I haven't check yet.

HTH!!