AllBlackSVT

I believe i have a faulty Voltage regulator, i have blown my 3rd alternator in as many months. The red battery light turns on and off based on my RPM and currently my battery gauge reads that it is over charged. Whenever i step on the throttle the battery gauge increases and the light turns on. I think it is the voltage regulator and whould like to swap it out. One problem, i have no idea where it is, or how to remove it. Im not even sure if it is external of the alternator. Someone wiser than me please interject. I have a 97 Cobra if that helps.

CobraStangGT16

The Cobra's for some odd reason always blow their alternators...

But my GT blew a voltage regulator too, like 2 weeks ago...Same symptoms, same diagnosis.

The regulator is located INSIDE the alternator, and you can't open it up unless you have the right tools which almost nobody has. What I did was take it to an Alternator shop and have them pull it apart, and put in the new one, then put it back together. Then take it home and install it, and it should be good.

They charged me $115 for a new one and install.

The genius' at Ford designed it so that nobody can change it themselves...ONLY the dealerships and alternator shops can do it...I know, it's retarded, but thats the only way to go.

pete97GT

whaaaat, 93 and up mustangs come with an internal voltage regulator, which means any alternator you buy will come with the voltage regulator, so if you had to replace the alt and you have the same problem then its obviously not the voltage regulator, as far as replacing it, i have never heard that you cant get to it and have to take the alt apart, as a matter of fact i replaced them myself. here is what your voltage regulator looks like: http://www.partsamerica.com/ProductD...amp;PTSet=Aits only a matter of taking three screws out. perhaps you have an overdrive pulley on your alt, which is just a smaller pulley a 1.5"or something, which spins your alt faster, it helps out when you have underdrive pulleys but otherwise you dont need it. Just a shot in the dark, but what i would do is go to an autoparts store look at the right alt for your car and make sure its the same as the one you have on there

pete97GT

correct me if im wrong but i am pretty sure the voltage regulator is not inside the alt rather it is mounted to the side of the alt, it is still an internal regulator however im pretty sure you can get to it fairly easily by unbolting the three or two bolts that hold it down

AllBlackSVT

Now ive seen everything. Started the car up this morning just to check it out, and the volts are stable, the light is off and there is little or no movement in the battery gauge when the RPMs increase. Yesterday the volts were up to 18 and everytime i hit the gas they would want to go even higher. Did i throw the volts out of wack for just one night by driving stupid?
Also i was curious if i changed the alternator does that mean im changing the volt regulator too? Because I had the alternator changed 3 times already and if that means that the volt regulator was also changed 3 times than i have another problem altogether.

ponysnake99

yes, you've changed the voltage regulator 3 times. When ford says there is an "internal voltage regulator" it means you can't go to ford to get a replacement piece, you will need to buy the entire altenator (except for the V6 has a replaceable one...dunno if you can retro-fit it). If you've had this problem with the previous altenators (no idea what caused u to change it 3 times) then its probably not the altenator directly, and the problem may be in another part of the charging system.

MrChubs1

I'm willing to bet you have a battery issue. Remember, the battery is the main resistor in the circuit. If it shorts internally, you'll fry an alternator very quickly. This situation doesn't sound exactly like that, but weird things happen. Try another battery to see if there's any difference. Easy enough to test!

CobraStangGT16

WRONG WRONG WRONG............ALTERNATORS ARE REBUILT....THEY CAN STILL HAVE PROBLEMS IF YOU BUY A DIFFERENT ONE!!! Thats the chance you take when changing alternators. They don't make new ones, and theres a good chance that you got 3 bad alternators.

Guys....this is a COBRA. They are notorious for blowing alternators, and the first thing to blow on the alternator is the voltage regulator.

AllBlackSVT....I know EXACTLY what you mean when you started it up and it was fine. Believe me, if you go drive it for 5 minutes, it will come back on. I PROMISE IT WILL. It happened to me for a week. You need to take the alternator off, then take it to an alternator shop....have them open it up for you, and they will know exactly what the problem is, even if it's not the voltage regulator.

You can't do it yourself, unless you have the tools to remove the bearing from the alternator and split it in half. You can't just unbolt those 3 bolts and open it up, I tried. Alternator shop will know how to do it right.

As for finding another problem....an alternator shop will also diagnose intermittant shorts, in case thats the problem. Cough up some cash and let the pros do it. I wouldn't risk doing it myself.

MrChubs1

Why then wouldn't a new alternator fix the problem?

I've rebuilt many alternators and never ran into anything too tough to take apart. That's just weird.

AllBlackSVT

I replaced the battery, and same problem, first it was over charging now its completely dead. Looking to get an alternator now.