Industry24

STFA----'97 A4QM 12v---92k


No other symptoms on start-up or while car is running except the ridiculous amount of fluctuating on the Voltmeter

About 3-4 months ago my car was jumped and the person connecting my car's battery put the wires on backwards,i know, WTF!Zapped the hell out of all the cars power.

So i took the battery to Autozone and recharged it. and it's been fine since (atleast the car starts-up fine). Then later, i took the car into an Interstate Battery to test the battery and alternator. Guy said battery is fine but with everything on, the alternator is charging low (think he said 12.5 w/everything on; 13.1 w/ nothing on).

Today i disconnected the battery to see if the car will continue to run and it did. the voltmeter climbed from about 12.8 to 13.5 & back to ~13 when i reconnected the battery.
I guess what i need is some opinions on these symptoms. I would really appreciate it.

Is there a short?
Do i need to make sure wires are grounded(how to)?
Voltage regulator?
alternator?
battery?

Thanks

ianbis

charging the battery. I know you had the battery tested twice but did anyone ever check the electolyte level?? I would start there. If its low add distilled water

Industry24

Wonder if that cheap (AutoZone crap) battery is was shorted or messed up but holds the charge B/c of daily cranking....

n0yxl

Time for a new alternator, maybe you can replace the diodes fairly easily; I wounldnt know on these cars.

Perpetual Novice

reverse connecting jumpers can cause rapid loss of electrolye, or in other words "Holy **** acids spraying everywhere!"

the test you did indicates the battery is drawing a huge current to recharge itself, either there are internal shorts, or low electrolyte, whatever, but it's definetely the battery. If the batteries taking that much, its on its way out.

If that batteries more than a year old, just go ahead and replace it. And when you do, be sure to rinse down everything in your engine bay. I would mix up a box of baking soda and gallon hot water, spray everything under the hood (including the underside of the hood, and especially under the battery where the vent line goes), and then do a normal engine clean/detail.

ianbis

Battery Water level = electrolyte level...

Industry24

what's going to kill me unless it's the regulator. Is that cheaper labor, STFA and it said good mechanic can do it in 30 min.


its been holding up....fine for 3-4 months. How long will it hold up, can i just keep driving?

rectifier diodes: are those replaced with voltage regulator?

Industry24

battery to see if that is the issue...But in the archives i read about how it might just be a waste of $$.

I was told that it only starts the car and after start-up it does'nt play a role...still tempted to get rid of it (crappy Autozone btry) & get something like the Interstate MTP-91 or something...don't want to waste mony though

Solaris

Could always DIY if you're up to it

Industry24

can do it (and alot of other things i want to get done) for good labor prices.

indie mechanic or someone who knows what their doing whether it be in their garage or a shop.

PPL love taking adv. of an audi owner