Double checking alternator problem
Thread Starter
Intermediate
Joined: Feb 2006
Posts: 28
Likes: 0
From: Eldersburg Maryland
Double checking alternator problem
Hi Everyone,
I have a 1990 with just 35K miles on it. This past weekend I drove it from MD to NY and back (used the A/C a lot for the first time in a long time, etc). On the way back, I noticed that the voltage gauge seemed to be pointing more towards the "8V" area vs its normal "middle" of the gauge. The next day I pulled it out of the garage to give it a bath and the battery indicator light on the dash came on.
I'm assuming this is saying that my alternator isn't working, correct?
I put a volt meter on the battery terminals (car not running) and got 12.06v. After I started the car, I was only getting 11.8v, etc. Shouldn't I be getting about 13-14v? I just wanted to make sure that it "most likely" is the alternator. There isn't anything else that could cause this, is there? The battery is relatively new (2yrs or so...a 72 month battery). Any info would be great. Thanks!
I have a 1990 with just 35K miles on it. This past weekend I drove it from MD to NY and back (used the A/C a lot for the first time in a long time, etc). On the way back, I noticed that the voltage gauge seemed to be pointing more towards the "8V" area vs its normal "middle" of the gauge. The next day I pulled it out of the garage to give it a bath and the battery indicator light on the dash came on.
I'm assuming this is saying that my alternator isn't working, correct?
I put a volt meter on the battery terminals (car not running) and got 12.06v. After I started the car, I was only getting 11.8v, etc. Shouldn't I be getting about 13-14v? I just wanted to make sure that it "most likely" is the alternator. There isn't anything else that could cause this, is there? The battery is relatively new (2yrs or so...a 72 month battery). Any info would be great. Thanks!
Burning Brakes
Joined: Mar 2010
Posts: 1,094
Likes: 68
From: Providence RI
Irony at its best...Put a duralast gold on my car right after I bought it in March 2010...
Driving home today, I hear a whine and the voltage meter drops.
Get home, open the hood, the alternator is all melted up and such. What a piece of JUNK. Luckily its a lifetime warranty. It got so hot, it put black marks on my valve covers.
Hope you buy a better brand than I did.
Thanks,
Mike
Driving home today, I hear a whine and the voltage meter drops.
Get home, open the hood, the alternator is all melted up and such. What a piece of JUNK. Luckily its a lifetime warranty. It got so hot, it put black marks on my valve covers.
Hope you buy a better brand than I did.
Thanks,
Mike
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
Buy a good rebuilt or modify it to use one from a 92-96 Lt-1.
I switched to a 94 alternator, and it's great. You get 35 more amps. higher idle volts with the AC on too.
I have an 86 coupe.
I switched to a 94 alternator, and it's great. You get 35 more amps. higher idle volts with the AC on too.
I have an 86 coupe.
Heel & Toe
Joined: Nov 2003
Posts: 22
Likes: 0
From: Colchester CT
Make sure you get a new or rebuilt alternator with at least 120 amps, preferably more.
To expand on this and maybe put more info on the table - I just had issues with my alternator - 87 coupe - and replaced it with a 125 amp unit. With a full load (headlights, A/C, audio and in gear at idle) I still see volts as low as 11.9 at idle. At driving speeds it will be between 13.3 and 13.5.
I don't know if this is normal and this could also be a heads up for 90Whitelightning for testing purposes when he installs new alternator. Any body got any ideas?
To expand on this and maybe put more info on the table - I just had issues with my alternator - 87 coupe - and replaced it with a 125 amp unit. With a full load (headlights, A/C, audio and in gear at idle) I still see volts as low as 11.9 at idle. At driving speeds it will be between 13.3 and 13.5.
I don't know if this is normal and this could also be a heads up for 90Whitelightning for testing purposes when he installs new alternator. Any body got any ideas?
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
I went through 3 under the original warranty and quit counting at a dozen. Yours was ancient for a factory alternator and probably a minor nuisance considering some of the other issues for this build (before 50,000 miles). The skinny when it was new was to carry a spare if your trip was over 100 miles. Depending on the quality of the rebuild, that may still apply.
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Le Mans Master
Joined: May 2004
Posts: 5,866
Likes: 60
From: Hellinois
Finalist 2020 C4 of the Year - Modified
I hear that, and I do ever since my little experience. I was leaving Illinois headed to Atlanta with the Vette and trying to outrun a snowstorm. I had just gone through the alt 3 weeks prior to this trip and in southern Illinois it decided to die on me,,,,, at 9:00 at night. After a flatbed ride, an extra night in a motel, and a bill the next day for $460. for a "hard to find" alternator I was on my way again,,,,, with snow on the ground.
Team Owner
Joined: Dec 2000
Posts: 21,094
Likes: 282
From: Phila., PA burbs
I went through 3 alternators in 3 years when I bought my car. I then took my alternator to a local rebuild shop. I'm not exactly sure what he did to it, but its been on the car for 8+ years now.
