Wanting to stall... runs rough... voltage fluctuates.

[Big Red '87]

I have a 1987 GMC safari that is in great shape but I noticed sometimes at a stop lights, or after a long drive then park for a while then start it up again, it wants to stall but most of the time it does not happen only runs rough for a bit and also while driving or idling the voltage gage drops sometimes as far as 9v and the oil gage goes crazy... then it's fine and runs normal. So I then I tested the Battery and Alternator extensively and they are both working perfectly any ideas?

thanks Dan

[kennysmoke]

Sticking EGR Valve?

[Big Red '87]

Would this cause voltage drop and oil gage to fluctuate rapidly.

[kennysmoke]

Yes... mine was doing it a couple weeks ago... as the van starts to stall you will see the voltage drop and the pressure fluctuate ....

[kennysmoke]

I had a chunk of carbon making mine stick.