Idle control valve
3 Answers
If the truck sat outside check for rodent damage to vacuum lines etc. Mice sometimes chew through vacuum line causing leaks and odd engine behavior.
Thks bob, but a pair of stray cats kinda call under the truck home, at least at night. I have done extensive visual inspection, nothing.
It is always a good place to start. I have had to remove the engine appearance covers on my trucks cause mice get under them and eat the vacuum lines. You might try to disconnect and reconnect the battery to reset the ECU and see if that helps.
