Sorry I apparently posted in the wrong place...My 1995 5.9 hesitates and sometimes dies just off idle.But runs great other wise.No codes..Changed IAC that helped but still there.Changed TPS-O2-MAP cleaned TB no change.Learned last night as long as its rolling idle stays around 300 rpm in or out of gear..Stop and idle goes to normal...
Any ideas..Thanks

 

That's too low. Reset the PCM. (just disconnect the battery for a few minutes.) start the truck, and let it idle for a few minutes. The PCM will relearn base values for the assorted sensors. Might solve your problem...

 

Thanks I'll try that...

 

well that didn't work..now it won't idle at all and runs rough until up to highway speeds...

 

Still idling too low? You have covered most of what I would expect to cause that.... How's your plenum? Oil consumption? Vacuum leaks? Getting any codes?

It might take the truck a bit to re-learn idle, but, if it takes more than a few trips to town to figger it out, something else is going on.

 

No codes..Plenum is clean..vac hoses good...Oil comsumption good for 200k miles..
I'm stumped...Checking comp now...Was running great no clues stopped at light on the way home and it quit...started right back up but wouldn't run at low speed...

 

Crank sensor or bad IAC I'll say. What brand parts/sensors are you buying?

 

I had that problem when my battery was starting to die. I got a new one and it fixed it. Probably don't apply but just something to think about

 

The crank sensor was next..thought about the battery too.had a van that did that its on slow charge.hate to say it but leaning toward pcm...still no codes....

 

Just a thought; Have you checked the fuel pressure, injectors, 39 psi is the number for a 95.