truck stalled...no start...jumped it... started ...ran for 2 minutes then started backfiring with no power...checked amp gauge 0 volts....disconnect battery cable stalled right out...installed new alter.and same thing...jumped it with power pack started right up ran fine till i disconeected jumper pack.it idles but rpm's are up and down and 0 amp's at gauge....truck will stall if i disconnect terminal...even with new alter.
any one have a fix...thanks,Ray

 

oh it's a 95 chevy 3500 hd dump truck...454 with 32,000 miles.that right 32,000.

 

Clean every connection in the start system especially the grounds.