5 replies to this topic

[BNaumann]

Just "finished" a new build and I'm getting 18+ volts at idle.  Google search finds this problem all over the internet, but I can't find a solid conclusion.  I spent most of the day trying to find the problem, not going to write a book here.  Anybody have recent experience with this and pinpoint the cause?  Is there an SM legal alteration that bypasses this flaky system?

 

P.S.  My plan right now is to run it Sunday and see if it shapes up or blows up.  Any input appreciated.

[FTodaro]

I would be interested to hear what the volts should be.

 

I think that the regulator is in the alternator it self, such that the remedy is to replace it. But someone smarter than me can confirm that. I am not sure.

[BNaumann]

I would be interested to hear what the volts should be.

 

I think that the regulator is in the alternator it self, such that the remedy is to replace it. But someone smarter than me can confirm that. I am not sure.

 

13~15V.

 

In the 99s the PCM is the regulator. 

[BNaumann]

New alternator fixed it. Sorry to waste the bandwidth.

[Caveman-kwebb99]

I had 18 volts once at atl burned up a camera I has wired in and smoked my kill switch and the got slower and slower

[BNaumann]

If anyone ever has a similar problem, I found running with the headlights on kept the voltage under the 16v it takes to turn the warning light on. Of course I don't know the exact mode of failure inside the alt - YMMV

P.S. Also, with the new alternator in my car the PCM reacts to loads to maintain the charging voltage at 14.70v. The voltage on the Red/Gray drive wire is about 0.5v idling, 0.75v with the blower on high, and 1.0v with the blower and headlights on. Hope this helps someone in the future.