Alternator Schenanigans

[Julian 641]

I've been having issues with the PCM messing with my voltage, so I spoke with Josh Over at mechman and he told me to see what happens when I disconnect it.. this is what happens.. this is something he has NEVER seen. As I say in the video it is not a self exciting alternator.

It is a brand new 320a alt.

[Julian 641]

I forgot to mention this is a PCM regulated car, so the PCM controls the output of the alt.

[KyleBrown 121]

well its working lol

pretty odd still

my buddy had a lot worse issues with his MM, highest it'll charge is like 13.5. they've done nothing to fix too.

hope you get it figured out

[ricksi30 923]

Weird.

[16K 159]

im sure theyll get it figured out for you....

[Julian 641]

I only did this to see what would happen if I were to externally regulate my alt, this is just a weird ass occurrence. Josh suggested this to see if anything funky would happen..

[altoncustomtech 773]

Damn, thing is defying laws of physics. Maybe you should disconnect the fuel lines and see if it keeps running on nothing?

LOL, J/K...

I gotta ask, was the alternator disconnected before the car was started? I could see where it might do something hard to explain like that if it was disconnected after it was started and charging already. If you started it after disconnecting it then I definitely have no good explanation for you. The voltage seemed to be pretty good and steady with it disconnected tho, maybe thats a good thing. Odd but good.

[ssh 924]

The other connection on the alt (covered by rubber jacket), is from the PCM?

If so, then I'm going to guess it's producing 14v. If that's the case, I wouldn't do anything that requires lots of current since your main power wire is disconnected, and it'll try pulling it through the small wire for the pcm.

At least that's my guess, but it's hard to really see what all is connected.

[Aaron Clinton 2,372]

Hope it gets worked out.

[Julian 641]

I disconnected the harness from the alternator and started it, Josh from mechman told me in some newer cars without the harness connected and the PCM controlling the alternator some bad things can happen to them. I am about to call him and see what he says.

[Julian 641]

The other connection on the alt (covered by rubber jacket), is from the PCM?

If so, then I'm going to guess it's producing 14v. If that's the case, I wouldn't do anything that requires lots of current since your main power wire is disconnected, and it'll try pulling it through the small wire for the pcm.

At least that's my guess, but it's hard to really see what all is connected.

That wire to my knowledge just runs to my battery up front. The Harness is what tells the alternator to turn on or off or modulate the voltage.

[edouble101 314]

The alt has an internal regulator set at 14 volts.

I had issues with an aftermarket alternator. My vehicles PCM wasn't able to control the voltage. I wired up an external regulator and bypassed the PCM and it works perfectly.

[Julian 641]

The alt has an internal regulator set at 14 volts.

I had issues with an aftermarket alternator. My vehicles PCM wasn't able to control the voltage. I wired up an external regulator and bypassed the PCM and it works perfectly.

I will probably be externally regulating it anyways.

[edouble101 314]

The alt has an internal regulator set at 14 volts.

I had issues with an aftermarket alternator. My vehicles PCM wasn't able to control the voltage. I wired up an external regulator and bypassed the PCM and it works perfectly.

I will probably be externally regulating it anyways.

You will need to have it sent back to Mechman for an external regulator setup.

[Sencheezy 689]

hope it gets worked out