I have an 89 F150 with stright 6cyl. At times it idles fine while at other times it idles alittle high at around 1100rpm. Anyone have any idea as to what could be wrong? Its like the idle sticks regardless if cold start or not.

Thanks

 

check your tps and iac sensors. first put seafoam in the brake booster to clean the gunk out of the tb and intake. also check to see if your throttle cable is sticking.

 

replied to the wrong thing

 

It's almost as if the throttle sticks. After first morning start if I shut off and restart it seems better. Also sometimes I can punch accelerator and this will idle down.

 

Any ideas?

 

might also check the throttle return spring and linkage. had a rig recently that would idle high and I'd tap the throttle and that would fix it until I got back on the gas. turned out the throttle linkage was coated in grime and the return spring may have lost tension. a little WD-40 and a tweak of the spring to make it a bit shorter and problem solved.

 

It definatly gets better if you shut the truck off and restart after initial warm up.

 

Could it be a sensor or spark plugs?

 

Where is the gps and iac sensors located? What do they do?