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Hello- I drive a 2006 ZX4 for work and while it's no Benz it gets the job done. However, it eats alternators like there is no tomorrow. I now have 105,000 miles on it and I'm in the process of replacing my FOURTH alternator. Ford factory unit made it to 47,000 miles. Bought the generic rebuilt unit when I found that the new Ford beast was $300 smacks in the head. It lasted 8 months. "Lifetime warranty" means I got another one but this job ain't like changing a headlight. That second one made it almost a year. Gave up on the rebuilts (got my cash back) and bought new to the tune of $200 pokes in the eye. That one went in the car on 5-7-2010 and I know that because that is the date on the receipt. So, soon enough I'll have my FIFTH unit in the car. The battery load checks fine, the wiring is good, grounds are clean and fuses/links are good.
When I remove the alternator they look fine- dirty but fine. What is it that eats these things? Heat build up? Water? This is becoming an annual event- the spring alternator swap and it's getting old, especially when it leaves me stuck on the road somewhere calling AAA for a tow.

UFM82
 

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This is kind of worse news, but there could be something wrong with your PCM (powertrain control module). Have you ever had this diagnosed or tested at a dealership? Forgive me if you know all this but I'm just voicing a theory. Old school alternators had an internal voltage regulator which basically dictates how hard it's working and what kind of voltage it's putting out. I'm almost positive that in all newer cars the voltage regulator is a function of the PCM or ECU, and it's generally better controlled because the PCM is better able to determine what kind of electrical load the car is under and how hard the alternator should be working. A faulty voltage regulator will kill any alternator.

On the other hand if the PCM was causing the alternator to significantly overcharge, it probably would have killed a battery or two along the way also. Just things to consider. I'd love to know what the problem really is, if you find out please post back here about it. Nobody wants to hear this, but you might be best off taking it to a dealership.
 

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I may have the same issue - alternator fried, then had it rebuilt by local rebuilder on advice of this forum. That lasted 2 WEEKS before the regulator failed again. Just got the re-rebuilt one back in two days ago.

During troubleshooting I checked: grounds, battery connections, fusible link, #10 fuse, alt wiring to PCM, and probably some more stuff only found two things that could be even remotely related:

1. OBDII Link Error when I try to pull codes - may dig into this soon.

2. Totally messed up wires going from the car to the wagon hatch. These could easily have shorted or back-fed voltage somehow. --> You should check your wiring there too.

Similar but totally unrelated to #2 - I have been driving Audi 4000's for many many years, and they are famous for guillotine-ing the wires that go to the trunk lid at the hinge. One of my cars did this and I discovered it when I started the car up, put it into reverse, then turned the key off and took it out but the car kept running!!! Had to take the car out of reverse to get it turned off - really freaked me out.

This is why I now suspect that my PCM is 'not right'.

Please let me know if you get yours diagnosed, and especially if there is a way to get this done without going to the stealership.

Tx.
-krashwaggin
 
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