Troubleshooting alternator problem

johnwartjr

Registered User
I am pretty sure I have an alternator problem.

Symptoms:

Occasionally (but with increasing frequency as time passes), my alternator light flickers.

It doesn't stay on, it just flickers for a second or two, and goes back out.

I did notice on my morning commute today that the dash cluster illumination was dim until the car had been on the road for a few minutes.

When the parts store tests it, the car is sitting, in park, no headlights, no accessories turned on, etc.

The guy at autozone recommended I take it to a local auto electric shop to have it diagnosed, as it's intermittent. He hooked his little machine to it, had me start the car, and tested the battery and alternator.

If it's bad, Autozone has to agree it's bad so I can collect my lifetime warranty and get another one from them at no charge.

If I have to buy another, it's not going to be from Autozone, that's for sure!
 
See my last post on page 2 of the below thread... you'll see my experience with Advance Auto yesterday :(

http://www.sccoa.com/forums/showthread.php?t=124645

You can take some readings @ the battery w/ a volt meter & if it's less than 13V, could be the alternator. On top of the alternator is a connector w/ 2 wires coming out. The green wire is a "monitor" to the regulator ckt. It should be the same voltage as what you see at the battery. The yellow is the power to the regulator / light. When the light is on, mine reads about 1.25 volts, when the light goes out, you should see battery voltage.

I'm getting a pretty good education on the charging ckt of these things, I've gotten to the point now that the car is just sitting there & I'm reading the shop & diagnostic manuals before going any further.

I know a lot of folks on here have been through upwards of 3 rebuilt alts before getting one to last.
 
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Autozone sold me the one on my car about 7 years ago. So, I'd consider that to be a decent life - but it has their limited lifetime warranty, so if it's bad, I want them to replace it.

Luckily, I'm pretty experienced removing and replacing the top intercooler tube, have had to do it a handful of times over the years :)
 
Autozone sold me the one on my car about 7 years ago. So, I'd consider that to be a decent life - but it has their limited lifetime warranty, so if it's bad, I want them to replace it.

Luckily, I'm pretty experienced removing and replacing the top intercooler tube, have had to do it a handful of times over the years :)

Me too, in the last few days ;)

Good luck to 'ya!
 
I am pretty sure I have an alternator problem.

Symptoms:

Occasionally (but with increasing frequency as time passes), my alternator light flickers.

It doesn't stay on, it just flickers for a second or two, and goes back out.

Welcome.. to Mitsubishi 110A Alternator hell!

Yes.. its bad and eventually it will go out completely, but until then you are screwed because it won't fail outright. What usually happens is the regulator goes out intemittently when it gets hot. Which is why it won't test bad when you take it in... it has cooled off.

Keep some jumper cables with you and a volt meter plugged into the cigarette lighter. When the voltage hits 11, start thinking about getting back to a charger, turn everything that uses power off.. headlights, wipers, window defroster, and stay off the brakes as much as possible to keep the pump from running (big power pull). Turn the A/C to OFF.

Unfortunately, there are not a lot of options when it comes to replacements. New ones are hard to come by, and remans are usually hit-or miss. Its not unusal to take 3 units to find 1 good one. My advice... get a used one from someone here... as most of those are/were still working, and then baby it at first.. keep the battery fully charged with an external charger before you run with any replacement. It lightens the load and keeps the heat to a minimum.
 
Well, my buddy who did the motor mounts hooked my car up to his test machine today, and it showed my alternator was putting out 63 amps, not 110.

Autozone ordered a replacement, and I can pick it up tomorrow. Once I install it, I'll go back for another test.

I've seen the alternator rebuild kits online for various cars, and I'd spring for one of those and buy a rebuildable core from someone here.. if there was a kit available! At least then, I'd know it's done right.

Is there an aftermarket alternator that fits that is higher quality?

I guess I don't feel too bad, got 7 years out of this one.. but I had the one that came on the car rebuilt by a shop, and it failed 2 weeks later while I was out of state. The Autozone in Chicago near my motel had one, and I paid a mechanic to change it in the parking lot (had no tools with me).
 
Is there an aftermarket alternator that fits that is higher quality?

No there isn't a direct replacment, that I'm aware of. There is an alternative alternator that will fit with minor modification. For more info Search "6G alternator" .

David
 
Autozone swapped out my 7 year old 'lifetime warranty' alternator, and now things are just peachy... til the next thing breaks :)
 
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