Hello. I have an '87 6.9IDI. Not sure of the true milllage but it's somewhere around 250k. The truck is realitivly new to me so I'm not sure if the IP is original to the truck or if it's ever been rebuilt.
The problem: After about an hour of highway driving if I pull off of the freeway it will idle high and choppy. Around 1000RPM. Feels like the timing is advanced. Almost a stumble. On short drives there's no problems. Steady idle around 750 and no surging.
I do not beleive I am burning oil, and both the high idle solenoid and cold timing advanced wires have been disconnected at the spade connections.
Does this sound indicitive of an IP problem? Could I be building too much pressure in the crank case? Or is it time for a compression test and a new motor?
The problem: After about an hour of highway driving if I pull off of the freeway it will idle high and choppy. Around 1000RPM. Feels like the timing is advanced. Almost a stumble. On short drives there's no problems. Steady idle around 750 and no surging.
I do not beleive I am burning oil, and both the high idle solenoid and cold timing advanced wires have been disconnected at the spade connections.
Does this sound indicitive of an IP problem? Could I be building too much pressure in the crank case? Or is it time for a compression test and a new motor?