Too much power from the alternator

[jnorion]

Yesterday my battery light started flickering on, followed by my brake warning light after not too long. I stopped by autozone and had them run tests and they measured 16+ volts from the battery terminals when I revved to a little over 2000 rpm.

I'm guessing this is just a bad voltage regulator and that I need to replace the alternator to fix it, but is there any other possible cause? Bad ground system (it looks fine)? Bad alternator plugs? Bad battery (it's old but seems to be fine when tested)?

It hasn't damaged the car yet but that much power makes me nervous. And I'm sure it's not good for the battery.

[Manarius]

Nope, I think your regulator is just shot and that the alternator needs to go. Bad grounds don't usually cause enough jolt in the system to throw a light.

[evolutionmovement]

Yes, it will fry the battery. This is the usual cause of alternator failures I find and it really sucks that you can't replace the voltage regulator seperately anymore, especially when the friggin alternators aren't cheap and any less-expensive 'lifetime warranty' bullshit store replacements have probably a 50% chance of failure within the first couple weeks. They don't warranty the labor of course. Douches. I'd recommend getting a used OEM from Blackbart or something. My original lasted 1/4 million miles, but the rebuild parts are more than twice the cost of a new OEM.

[jnorion]

OK, I'm gonna try for Blackbart's alternator. Any ideas how long I can push it while I wait for shipping from Pennsylvania?

[scuzzy]

OK, I'm gonna try for Blackbart's alternator. Any ideas how long I can push it while I wait for shipping from Pennsylvania?

I wouldn't drive it.

Period.


the ECU and other components are sensitive to input voltage, you're two volts over rated voltage, ECU's cost in the ballpark of $250 - assuming you can find one.

[jnorion]

OK, good enough for me. Dammit. I think I have to cannibalize the wagon while I wait for a new one. I need at least one car working properly.

[jnorion]

This morning I swapped the alternator from the wagon into the sedan and everything is working properly. Tested with the multimeter afterward and it maxed out at 14.4 volts. I was stupid and managed to break one of the tensioner bolts in the process, but the wagon won't be running without the alternator anyway so I have time to find a new one.

[mattyg41383]

Im getting the same problem now... Brake and Battery indicator lights are coming on for a short while. So it appears that the AutoZone alternator I got stuck having to use is crap after only 5 months.

Are the alternators from a '90 NA and a '93 turbo interchangable???

[evolutionmovement]

I believe the connectors are different, but I'm sure you can get them to work. A used OEM alternator is almost always better than any chain store junk.

At least this is on a Legacy. My friend did this on his Audi - a $600 job that requires the whole front of the car to basically be removed. Could have been a fairly easy job, but German engineers are pure suck and they didn't put a simple hex bolt that would have been somewhat easy to access, but some other piece of shit you needed the radiator and, subsequently, a bunch of other shit removed for. It then had to be done twice as the replacement failed in three days. At least the three hundred dollar+ alternator was warrantied. Yeah, the original alternator died at 65k.

Anyone want a 2001 Audi A4 Quattro turbo? Engine hasn't blown from oil pick up issues yet. Has some cool wheels.

[mattyg41383]

yeah the only reason i got stuck with an autozone one is that my original one crapped out 2 days after i got it on the road, and it stranded me near the store. Its only a 10 minute repair, so thats the good thing... and Pops said he's got a few OEs sitting around the shop that I'll use.

i dont think there's anything easy about working on Audis