This problem just started, but it doesn't always do it. When I shut the truck off it starts dieseling. Kinda like the car from the movie Uncle Buck but without the backfire and smoke. It started after i hauled a slide in 10 foot camper from the 70's about 40 miles. That wa a week or so ago, and has done this dieseling thing about 7 times since.... what is causing this? everyone is tellimg me th change my thermoustat (sp?) but would that cause it? the onl;y gauge in my truck that seams to work good is the speedo and gas... temp, oil and volt never seam to read different after truck is warmed up or hauling a load. Any help please, i need it....

Jim

 

1. SPARK PLUG WIRES NEWER
2. HOW MANY MILES ON THE MOTOR
3. FUEL USED COULD BE BAD
4. CARBERATOR COULD BE SHOT

 

My 87 w150 does the dieseling thing once in a while too... now im almost thinking that it might be a faulty ignition switch in the steering column not totally breaking the connection well enough to kill the motor but allowing enough spark to turn the engine over a couple few times before it finally stalls itself out. If you figure it out let me know how it turns out!

 

The timing might be too far advanced. Get a timing light and check to see what it is set at.

 

I really doubt this may be it.
JMO

 

It has not done this in a while now.... i ahve another problem now.... leaking gasket on the water pump... easy fix, just don't wanna do it.