Ranger idels rough on startup..
Need some advice..
I have a 94 Ford Ranger that is idle rough at start-up. It only does it when the truck has been turned off for several hours, mainly overnight. When I start it in the morning the RPMs jump to about 2500 and then immediately drop back to 500ish, and the engine almost chokes out. It does this two or three times and then it idles back to normal RPMs. I was thinking maybe this could be caused by the Idle Air Control valve or the Throttle Position Sensor. Anybody have any advice or suggestion.