Well the other day I installed my HIDs. So I undid the negative (-) side of the terminal of the battery. I finshed up and my lights worked, etc. But upon startup and warm up, I noticed that my truck isnt idling at the normal 800 rpm but like 640...then 720....then down to 670....then up to 705...like jumping around. Then I kick on the A/C to see what happens and it drops as low as 530! It sounds as if its going to stall. When I drive around and go back to idle, it will sometimes stay at 800, I drive some more and go to idle, this time it acts up again. Its totally random and the only thing I did to it was unplug the negative terminal. How could this mess up my idle? I think I might replace the plugs and wires next week.

 

SAME thing is happening to me right now. I've been searching for the correct idle speed at operating temp for half an hour but to no evail. I have a hayne's shop manual but can't find it. I was thinking around 775-825 was normal?
truck is shutting off on me sometimes becuase it idles too low. Even when cruising, if I am not on gas sometimes it shuts off because it idles too low. I think i am going to go to auto zone for a diagnostic soon....if this keeps up im going to wreck via not being able to turn and brake as good.

 

Check the Idle Air Controller... it's that shiny thing right after the rubber intake mounted on the throttle body. It might just need to be cleaned/replaced.

 

When's the last time you cleaned your throttle body? Mine all of a sudden started doing the same thing, then I cleaned the throttle body and it runs like new!