Thanks for reply, Alloro.
1.no noticable exhaust color - if I had to say one, I'd say barely white (saw this once many months ago)
2.Unknown if crank sensor is OEM; looking at it I'd probably guess it's original
3.Unknown if pickup coil is original; cap has been replaced
4.Coolant level is always in same level in recovery tank; radiator is always full.
Flushed and replaced coolant last summer. No cooling or overheating issues.
I think I see where you're headed in your thinking....Head gasket? Or a timing issue,
either spark or fuel injector? I've noticed in several threads of this forum that a faulty crank sensor can cause many unusual problems with these Vans. And why
oh why, didn't Dodge include an OBD II code for crank sensor? Will check my Haynes for crank sensor tests. What about the pickup coil? Just replace, or what? Thanks again. You are really helping me.