High RPM after start

[Nobby]

When it happens, I stop and restart and all seems fine. I've scanned for codes and nothing shows.

When it does the RPM rises to 1500-2100 cause shifting to be hard.

I'm leaning to replace the throttle position sensor but since no codes, I'm a bit confused. Could it be cleaned?

Any suggestions?

[procaddytech]

Check to see if a cruise control or throttle cable sticking holding the throttle blade open or is the throttle resting on the stop screw If the throttle blade is fully closed your IAC valve may sticking in its bore or just going bad. If you have never cleaned the throttle body and IAC valve and bore you should do it anyway. A vacuum leak should do it all the time but they should be checked for also. If you have secondary air injection the idle is high when first started but only to 1,100 - 1,300 rpm.

[ND4SP]

Originally Posted by Nobby

When it happens, I stop and restart and all seems fine. I've scanned for codes and nothing shows.

When it does the RPM rises to 1500-2100 cause shifting to be hard.

I'm leaning to replace the throttle position sensor but since no codes, I'm a bit confused. Could it be cleaned?

Any suggestions?

I had the same thing happen to my 1999 3.5L. It went on for a long time, finally replace the throttle position sensor, problem solved.