Different? Idle Question

[smac61]

I tried search but no luck. I have a problem a little different than those I have seen on the board. Normally I have no idle issues. Lately on cold start, I get very minor fluctuations, around 50 RPM if I had to guess. If I drive for 30 minutes or so, then shut it off and restart it 15 minutes later, I get fluctuations around 500 RPM, and most times it dies. Sometimes it starts jumping around if I have to sit at a long traffic light. I have to monkey with the gas pedal to get it to smooth out.

I have cleaned the IAB, checked the TPS (.95-.96), and I have the idle adjuster plate. No engine codes. I have found no obvious vacuum leaks, although I am suspicious of the line from the charcoal canister to the intake.

Anybody have a clue?

 

[sublime29]

Hello! I would guess it would be the throttle body not adjusted properly.The idle is not adjustable on the 5.0.The screw on the throttle body is a throttle stop screw.It prevents the blade from gettin stuck.It should be closed and adjusted so the throttle can be floored let off fast and close without gettin stuck at all but not lettin air by.Then check the TPS voltage.Then check timing and vaccum.Try to get some throotle body cleaner and clean out the throttle body and spray in the idle bypass valve real good. Later Sub