Since this seems to be such a hot topic!

AT Idle, (WITHIN FIRST 3-5 Minutes drive time), will go above 1000rpm which in-turn causes the ECU to momentary cut off fuel to the engine.

Resulting in - Idle drops about 200-300 rpm. Then slowly climbs above 1000rmp. Repeat! Does this about 5 times WHILE ENGINE IS STILL WARMING UP.

Now, I know, if I lower my idle with the idle set screw. This would stop.

Problem is, currently the truck when ENGINE IS WARM (driving for 15 minutes or more), idle is about 800-850 RPM. Sometimes lower, if I coast to a stop with the clutch to the floor (700-800rpm).

So, If I lower the idle speed, it will then cause my truck to idle (lope) even worst. It would fix my Idle shut off during warming up, but once the engine is warmed up, my idle then would be TO LOW.


I'm assuming there is a sensor controling my idle speed, which may be getting info from my Coolant temp Sensors. Both coolent temp sensors are new (The sensors in front of the engine, behind the fan.)

Any Ideas?