i have a 1986 suburban with a few quirks, nothing that has become a full blown problem yet

problem 1: sometimes, usually when cold, the truck will idle higher than usual

problem 2: sometimes the truck will accelerate on its own, usually while i am trying to gently accelerate it will take off like i put my foot to the floor (might actually take off harder than if i did put my foot to the floor)

problem 3: sometimes if i shut the motor off while its fully warmed p and come back before its completely cool, it doesnt like to start without lots of cranking, glow plugs do not come on - otherwise starts on the first crank

problem 4: i think this might just be inherent in these low power diesels, anything from half throttle on just makes more noise and doesnt seem to create more power

i think these problems might be all related, but who knows they might all just to be expected of a detroit diesel, this is my only diesel so i dont really have much to compare it too

thanks for the help



oh and the rig is straight piped if that might make any difference?

 

Sounds like PMD.

 

No pmd on 1986.
The truck Idling high when it is cool means your cold start is working. It accelerating hard I can't answer could be a injector pump problem or the governor might just be upping the fuel. I don't know why it cools down fast and don't know if you could ever fix that. The part about it not having any more power if you put it all the way to the floor is probably just the trucks lack of a turbo.

 

I had the same problem on a non-turbo IDI recently turned out to be the IP timing. Half throttle produced more power than full throttle and I had weird throttle responses often also.

 

Not sure if they put a TPS on Pump if they did could be bad


Hard start on hot motor next time pure water over then IP and see if it start up easier if does say it bad IP