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2G 3rd bad alternator - ECU to blame?

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952g63t

10+ Year Contributor
401
34
Mar 19, 2012
Summit Point, West_Virginia
First was OEM, second was a re-maned Galant alt, and now another brand new f'n OEM alt is going out on me.

What the hell is going on with this shit.

The alt was running before a recent motor rebuild, which previously was literally like a month old. Currently running a Jay Racing relocation kit and a very small amount of electronics, a few gauges and a regular head unit, no amp, etc.

It worked for about a week on the new setup and the other day my running volts starting going down until the damn car just doesn't want to run normally any longer.

There has to be something more to this than a few drops of power steering fluid or some other BS.

I am at my wits end with the alternators and this facking car.

Is there a way I can verify the ecu electronically rather than just visually? It looks fine but I suspect something to do with the Green – Pin 41 on the ECU – Voltage Regulator FR? OR White – Pin 33 on the ECU – Voltage Regulator G? or the alt relay on the harness? Is the alt relay suppose to be grounded by the little metal bracket it bolts up with? Mine was damaged so I just let it dangle.

I am going with a gm/Saturn alt this time for the better voltage but I need to figure out what is causing this before I fry another one. :mad:
 
Did you do a voltage drop across the power wire? Or check the resistance of it?
Battery @ start: 12.8v
Starts and runs great at first, then voltage starts to drop to 12.0 then 11 then 10+/- then it starts to idle like sh** and cuts out. No voltage change when I rev, it just falls.
 
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How Many grounds do you have? You may need to add or really check the wiring. Sounds like somthing is shorting out somewhere in the track. And pretty sure the relay is supposed to be bolted down for grounding perpose. Can you post a pick of yours?
 
How Many grounds do you have? You may need to add or really check the wiring. Sounds like somthing is shorting out somewhere in the track. And pretty sure the relay is supposed to be bolted down for grounding perpose. Can you post a pick of yours?
My ground cable goes from the battery to the block and then I have a cable that goes from that point to the body. New cables, good connections, etc. Would adding one to the body from the battery make any difference here?
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What about the ground around the throttle body there's 2. One ground should go from battery to starter bolt or the one next to it on trans, one of the 2 LOL. Then you want one to go from battery to body.

Yeah, I don't think that makes much difference where the cable is on the starter bolt or the block. The throttle body ground? Not sure what you mean here, got a picture? I have one small ground cable that was attached to my old intake manifold for radio interference? That one is not connected.

If I need to add another ground cable, wouldn't it be better to use that unused post on the alternator?
 
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O a continuity test from alternator to ecu and make sure no other wires are shorting out once you've done that then go ahead and buy an ecu.
 
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