Alternator probs, experts in electrical needed

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01-25-2018, 09:30 AM

#21

ryansmoneypit

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Quote:

Originally Posted by Ted75zcar

Just for a detail point, while the NA alt has a built in regulator, the feedback for the regulator (at least on the early NA) comes from the load side of the inj fuse. The alternator may have a protection mechanism that prevents them from charging if that fuse is blown. If the VVT solenoid is common with a sneak path to the injector fuse net, high current there could smoke it.

Great thoughts here for sure, but the car still starts and runs well- until the battery dies. I do agree that there must be a sneak path because lighting up the VVT wire from a short at the INJ fuse is strange.

On a good note- MS# does not apear to be burned at all. Like the system just used the VVT wire as a giant fuse.

01-25-2018, 10:12 AM

#22

Ted75zcar

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I think it is possibble would run if the sneak path impedance is low enough and the diodes are capable of conducting the necessary current. Have you ohm'd out the INJ fuse?

01-25-2018, 10:22 AM

#23

ryansmoneypit

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Quote:

Originally Posted by Ted75zcar

I think it is possibble would run if the sneak path impedance is low enough and the diodes are capable of conducting the necessary current. Have you ohm'd out the INJ fuse?

I will do that tonight. well, ill try to. Last time I tried to test it, I think I did more damage. Maybe I should just BUY a new fuse.

01-25-2018, 10:24 AM

#24

Ted75zcar

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Physically remove the fuse from the car. I would also question the main relay, but I think we know there is voltage on the output side there. IIRC you need voltage on the INJ net to turn the main relay on.

02-05-2018, 12:37 PM

#25

ryansmoneypit

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UPDATE: I replaced all of the little light bulbs in the gauge cluster, cleaned and reattached all the ground cables, tested all circuits. Nothing. everything tests good (continuity) except for when the alternator signal reaches the cluster. somewhere between signal in and the light bulb, I lose continuity... now Im stuck again. In one last ditch effort, I took the new, rebuilt alternator back to NAPA. It was DOA. They weren't surprised, gave me a new one and everything works again. Go figure. Weeks of trouble shooting only to dismiss the fact that a new part might actually be no good.

For now, the car runs really good, but I am skeptical. In one year I had: the stock Alternator die, got one from VatoZone that started spitting out 20 volts, then a DOA from NAPA. coincidence, or is there a deep rooted problem hiding ATM.....

02-05-2018, 12:52 PM

#26

lsdlsd88

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definitely not the first time I read about BAD "rebuilt" alternators.

magically when you get a new OEM it lasts the usual 15 years...

02-05-2018, 07:52 PM

#27

Gee Emm

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I had the same problem out here, went through two replacements before I got a lightweight race alternator. The shop that got that for me was coy about source/donor so I can't help there, but it solved my problem, and saved weight/space to boot!