why does car idle high? on 1996 Dodge Intrepid

why does car idle high and then back to normal and then idle high again? check engine light stays on.

Asked by for the 1996 Dodge Intrepid
If the check engine light is on then the control module has detected a problem, and that problem is likely causing the idle issue. Have the codes checked and a diagnosis performed by a shop to find the problem.
I am having the same problem. I've replaced a ER value senor and a crank senor. Car still idles high and at stops runs really rough, to the point where it sounds as it is going to stall. It was given me code but not anymore. Anymore ideas to try?
1 more answer
my dodge ilde good until you get to 1100 rpm then it go up and down i got 2 cods p1391 po123 but the car still paulsate at 1100 can some one give a ancswer