Alternator?? Help please! I'm stumped
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Alternator?? Help please! I'm stumped
Had a bad alternator about 8 months ago. Replaced it with one from the parts house. Ever since the batt light flickers and acts like its just borderline coming on or staying off. It been getting worse and worse. The other day coming home i noticed all the lights went dim, radio off. I pulled over to check voltage at batt. 12.1 
I waited 20 min there at idle and then took off fine. Got home decided to replace the cable first. Replaced batt showed 14.2 to 14.4. Perfect. I drove 4 miles to get something to eat and it died on my again with no voltage at batt. Just 11.9. Auto Zone tested it twice and it passes all test....... What do I do now?
I waited 20 min there at idle and then took off fine. Got home decided to replace the cable first. Replaced batt showed 14.2 to 14.4. Perfect. I drove 4 miles to get something to eat and it died on my again with no voltage at batt. Just 11.9. Auto Zone tested it twice and it passes all test....... What do I do now?
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Joined: Jan 2011
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From: Spokane, WA
Absolutely agree with billmck04. Clean those ground points. In fact, clean all the connections. Both ends of the positive and negative battery cables, hot leads from the starter solenoid, block to body grounds, etc. You never know. If that doesn't get it, must be the alternator somehow. Good luck.
Last edited by BLS; Jun 18, 2011 at 03:12 PM.
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Joined: May 2011
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How's the connector at the alternator? You may need to replace the plug and as much of the wire as you can with the replacement pigtail.
First thing after checking that is the grounds. Physically take them apart and clean them, even if they don't look bad. I personally like to put a nice coat of dielectric grease on them too. Don't go buying that expensive stuff labeled dielectric grease either.... get the silicone brake caliper grease. Same stuff and usually cheaper.
If that doesn't work you might need to check the wires going up to the dash light. I've seen issues with them before.
Had a Taurus recently that was going though the shop's techs like crazy. When it was my turn to install alternator number four, I replaced the pigtail to the alternator, cleaned and greased all the grounds, as well as checked the wiring to the dash light. Alternator has worked fine for months now. By the way, there was no clear indication of why this ate 4 alternators. All the grounds seemed decent and the plug seemed ok as well.
First thing after checking that is the grounds. Physically take them apart and clean them, even if they don't look bad. I personally like to put a nice coat of dielectric grease on them too. Don't go buying that expensive stuff labeled dielectric grease either.... get the silicone brake caliper grease. Same stuff and usually cheaper.
If that doesn't work you might need to check the wires going up to the dash light. I've seen issues with them before.
Had a Taurus recently that was going though the shop's techs like crazy. When it was my turn to install alternator number four, I replaced the pigtail to the alternator, cleaned and greased all the grounds, as well as checked the wiring to the dash light. Alternator has worked fine for months now. By the way, there was no clear indication of why this ate 4 alternators. All the grounds seemed decent and the plug seemed ok as well.