I just bought this 1988 chrysler lebaron automatic and the first day it ran a little rough I got the oil changed checked sparkplugs and wires and distributer. Everything seems fine. When I start the car it takes a minute or two to get going. It has a high low rythm and then after it warms up it idles very high like it wants to jump out of the car andtake off on its own. What could the possibilites be.
The first thing I'd check for is a vacuum leak. The Engine Computer controls idle speed through the automatic idle speed motor which is a controlled vacuum leak around the throttle blade. It may be trying to compensate for the high idle resulting in surging. Pinch off various hoses to see if one brings the idle down. You can also spray water on the hoses and gaskets while the engine is running and still cold. Watch for it getting sucked in or listen for the speed change.