So, its very hot. Im finally running my AC now but am having idling issues. I turn my AC on and the idle drops like crazy. No tach at the moment, but it drops to the point that when the engine is at operating temp it will almost and has died. Ive brought my idle up like three turns of the screw, but I turn my AC on and the idle drops like crazy, again. It idles low after I turn the AC off, but if I bump the throttle it will idle back at the normal speed. I posted info on another thread and heard that heat and a worn IP can cause a looooow idle. Soooo, I let it idle crazy low and took the hose to the hot pump and within 10 seconds----shazam!----idle comes up . Is it a dying IP? Where should I go for a rebuilt one? Are their any upgraded pumps? Im in AZ...two clicks from heck.

 

Don't panic yet, they all idle slow when the fuel is hot. Try bumping the idle up some and see if it will maintain an acceptable idle speed hot but not race when it's cold.

 

The exact same thing has been happening to me... I've turned the idle up to about 900 (sometimes my needle is a little jumpy) in park, around 750-800 in drive. The truck runs great at high rpm on the highway but if i stop the truck to fuel up it will sometimes have a hard time starting i have to put the pedal to the floor and crank for awhile before it will turn over then if i've had a hard start up it will often stall when i put it in gear. it has seemed worse the last couple of times i've driven and it's been real hot out. i've had my suspicions about the IP as i've checked the lift pump and it is reading btw 7-8 psi. Any thoughts?

 

Sounds like yours is about done for.

 

Well I did what any self respecting cummins owner would do in this situation...I turned the fuel screw in another half turn! Its so much easier getting to the fuel screw than the idle, especially in the dark. LOL

 

Now that's thinkin'!

 

That a boy Mike using the ole noodle