YACT: 90 Caravan, electrical/ignition issues?

[ThisIsMatt]

Ok, my sister has a 90 dodge caravan. Lately it has been dying, especially at idle, but even sometimes in the middle of driving.

I just fired it up and it was idling fine. I put a voltmeter to the alternator and battery and got:

Alt: 20v DC, ~43v AC
Batt: 19.4v DC

Both of these DC volts seem a little high, and I'm also wondering what the AC voltage could mean.

I cranked the vent fan all the way on, turned on the headlights, turned on the radio, then rev'd the engine a few times and then let it fall back to idle, at which point it died. During the reving I could hear what sounded like a relay kicking on/off at the right side of the engine bay (where most of the electrical is).

Any ideas? Bad alternator?

 

[ThisIsMatt]

anyone?

 

[Evadman]

Your voltage regulator and/or rectifier is bad. Replace alternator and battery. It doesn't take long to kill a battery trying to stuff 20 volts into it.

 

[Pepsi90919]

the alternator seems to be putting out too much voltage.

the ridiculous AC voltage could be a diode that's gone bad.

 

[thedarkwolf]

I agree the alt has gone funky

As for the other problems run the codes
http://minimopar.knizefamily.net/fault/index.html and see what comes up.