Orange Peel

iTrader: (20)

My wife's '00 TA is an A4 and her battery voltage sucks *****. I just replaced her battery today with a Red Top Optima battery, since the GM battery started to leak acid all over the garage floor. Here's the break down of her voltage....

WITH OPTIMA:
Idle in park with a/c off: 13volts barely
Idle in park with a/c on: 11.5-12volts
Idle in gear with a/c on: 11volts maybe, right above the yellow area
Cruising down street with a/c on: 12volts area

When it's REALLY hot outside and you are at a light with the a/c on it will be at the line where the yellow starts. What the hell is going on here?

My SS (6 speed) will idle over 13 volts all day long. I know it has less load, but are all A4's this shitty?? I plan to get a Yukon alternator for her car, but just want to make sure nothing else could be wrong. I may need to replace some of the wiring, the flat metal thing that the terminal bolt goes through is yellow and discolored due to the corrosion, so I may need to get a new one of those.

Thanks for any help!!!!

Ragtop 99

iTrader: (7)

I have the opposite problem. My voltage is really high when I first start out. During the winter, I'll hit the right hash mark. I assume its a bad voltage regulator (been through 2 batteries already).

stock A4's do idle lower than an M6.

Orange Peel

iTrader: (20)

What is the voltage regulator and where is it located? What does it do? I have never heard of it, it could be bad on her car too.

1QUIKWS6

iTrader: (61)

The voltage regulator is internal to the alternator. It senses the need (or lack thereof) for voltage, then either steps up the voltage or cuts it back.

SmokingWS6

iTrader: (1)

I run normally at 13.8 volts in park or drive at a stop. only time it dips is when the a/c is on and the cooling fans are on high, then it'll drop to just above the yellow in drive at a stop. 12 volts or so. This is normal. but it sould go back up past 13 as soon at your over 1000rpm or so.


Sounds like you alternator needs to be replaced and or the battery acid ruined your cables.

Orange Peel

iTrader: (20)

Yeah hers isn't that high in park either. I am most likely going to get a Yukon alternator that is 160amps, and be done with it. Damn A4's

SmokingWS6

iTrader: (1)

I duno if it'll fit. If it does let me know. I've got some friends with systems that could use a larger unit.

Orange Peel

iTrader: (20)

People are saying that the Yukon, Sierra, Etc with the 5.3L alternators directly bolt into our cars. And at 160amps, that would be sweet!!!!