Electrical Altenator Keeps Blowing Regulators Please Help!!

fiveohlover

Member
Oct 13, 2011
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mn
I let my son hook up my battery on my 86 gt last year and he hooked it up backwards. He thankfully saw the smoke that it made and unhooked it right away.

The car started right up after i installed it properly. Went for a drive and all of a sudden noticed less power and lights dimming and my radio started acting up funny and then car died. I came back next day with a spare battery and drove it home. I had the alternator rebuilt and installed new regulator on it. Thought it was fixed and drove it for a while again and the alternator was charging and working properly after the rebuild then it blew the regulator again, (guessing it over charged the battery and blew itself out) and i was running off of battery power again until the car died. Had the alternator checked out again and did the exact same thing. Can this be a bad alternator? Or is my computer messed up and i need to get a new one? any ideas?
 
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The smoke probably was an indication of some wire or part burning somewhere. Did you find and replace or repair the burnt components or wire?
 
It is a ford motor craft alternator with a internal regulator. I have had it rebuilt 2 times by a local mechanic. I think its stock wiring not sure because i bought the car a few years back. No i haven't found any wires that needed replacing yet
 
You said smoke, and that means something got hot enough to almost catch on fire. Find where the smoke came from and that is the most likely source of your problem.
 
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not sure why but your attachment doesn't work for some reason
This is a ongoing problem that the Stangnet team hasn't fixed yet. Or maybe they have, but I just don't understand what the fix is.

@MRaburn @Noobz347, see my post above with the x in the box instead of a picture. I know that we have had this discussion in the past. My attachments have grown to 74 pages, about 62 pages of that is duplicates of things I had already used in the past. The link to the picture was a JPG that I uploaded several years ago and has worked without problem until about 3 months ago when the Forum software was changed. Please fix or explain in simple terms what I need to do to fix the problem. As it is now, I have to upload a picture or drawing every time I want to use it, even if it has been uploaded before.
 
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Check the fuse links, I reposted the drawing.
If fuse links are good and computer can dump codes, post the results with the code numbers. If the codes dump and there isn't a code pointing to an internal failure the computer is probably OK.




Dump the codes: Codes may be present even if the Check Engine Light (CEL) isn't on.

Dumping the computer diagnostic codes on 86-95 Mustangs

Revised 26-July-2011. Added need to make sure the clutch is pressed when dumping codes.

Codes may be present even if the check engine light hasn’t come on, so be sure to check for them.

Here's the way to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.

Post the codes you get and I will post 86-93 model 5.0 Mustang specific code definitions and fixes. I do not have a complete listing for 94-95 model 5.0 Mustangs at this time.

Be sure to turn off the A/C, and put the transmission in neutral when dumping the codes. On a manual transmission car, be sure to press the clutch to the floor.
Fail to do this and you will generate a code 67 and not be able to dump the Engine Running codes.

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If your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

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The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.

89 through 95 cars have a working Check Engine light. Watch it instead of using a test lamp.

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The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.


WARNING!!! There is a single dark brown connector with a black/orange wire. It is the 12 volt power to the under the hood light. Do not jumper it to the computer test connector. If you do, you will damage the computer.

What to expect:
You should get a code 11 (two single flashes in succession). This says that the computer's internal workings are OK, and that the wiring to put the computer into diagnostic mode is good. No code 11 and you have some wiring problems. This is crucial: the same wire that provides the ground to dump the codes provides signal ground for the TPS, EGR, ACT and Map/Baro sensors. If it fails, you will have poor performance, economy and driveablity problems

Some codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Dumping the Engine Running codes: The procedure is the same, you start the engine with the test jumper in place. Be sure the A/C is off, and clutch (if present) is pressed to the floor, and the transmission is in neutral. You'll get an 11, then a 4 and the engine will speed up to do the EGR test. After the engine speed decreases back to idle, it will dump the engine running codes.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

Your 86-88 5.0 won't have a working Check Engine Light, so you'll need a test light.
See AutoZone Part Number: 25886 , $10
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Alternate methods:
For those who are intimidated by all the wires & connections, see Actron® for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.

Or for a nicer scanner see Equus Digital Ford Code Reader (3145) Equus - Digital Ford Code Reader (3145It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $22-$36.