Randomly my truck has been starting to idle reallllly low, to the point of almost stalling out. Normally in drive my idle is around 900 and randomly at a stop light or in traffic it will drop really low. Ive noticed that it'll do it when stoped on a decline too. First thing i thought to do was change the fuel filter, but i thought id ask on here first. I had the idle set to where it's at about 3 weeks ago because it was always idling very low, and now everythings fine except for a few seconds when at a stop light...

any ideas?

 

I'd check the fuel lines, lift pump/fuel heater, and overflow valve.

 

What he said..

or if uve messed with ur Governer springs, or put a spring kit, they might be a wee bit too loose...

RIck

 

What he said too, also unplug the wire harness that plugs into the fuel heater to see if there is fuel on it. If there is you are sucking air through the heater, it will need to be replaced....