high idle problem

[redrocket1468]

at times when i come to a stop the idle stays around 1300 if i snap the throttle it goes down was wondering what is wrong

 

[mechjames]

Could be the throttle body not fully closing, Sticking idle air control valve or vaccum leak somewhere.

 

[Chilton Nystoruk]

hahaha just the post i was looking for, I've got the same prob, just started happening a day or two ago on 94 explorer obd1 of course, only i waited five minutes and it didn't go down, and snapping the throtle didn't help either, only thing that returned it back to normal was shutting the truck off and starting it right away...... doesn't seem like anything is sticking otherwise shutting the truck off and restarting wouldn't work right??

 

[MuddHungry]

I agree with MechJames. I had the problem with the vaccum leakage when I rebuilt the top end of my engine.

Yet this happened more recently:

I just repainted my floor and put cardboard inserts on the front floorboards rainy wetness on "new" floor, not good. Well the one on the drivers side kept slipping up and making the throttle stick. Also I had recently taken off my Poly Intake tube and cleaned it out and such, and when I put it back on the Rubber gasket was just a little bit too high on the throttle body inlet and slightly held open the Throttle body linkage. Started just fine, but when you press the gas it stayed about 1/16th of the way open. Not very much but, well it makes a difference. Same thing about the high idle and then the correction with the snap of the throttle. But I got tired of it and went investigating. Well needless to say I found the problem

Does the engine continue to rev instead of just idling higher? Have ya done anything to the intake lately? If so, disconnect the battery for like 30 seconds and re-hook it back up. I really dont know how long you have to leave it disconnected for but 30 seconds always works for me.

 

[YBCold]

i was having this problem recently when it was really hot out here. it had a tendency to have runaway RPMS when i shifted into park after driving in my parking lot.

 

[boggs1227]

my 2 cents .....i agree with the sticking throttle body linkage but also the tps sensor could be a cause as well . on newer explorers i think the tps sensor "zeros" out when the ignition key is first turned on (self calibrating)
but on the first gen explorers thats not the case .the sensor has a preset range to work with so if thers any bad spots on the contacts inside the sensor it can send garbled data to the computer to control idle speed .mine kinda does this (aftermarket tps sensor) be fine one moment then kicks up to say 1k rpms brieflly then back to 700 rpms .

almost did not find the problem till i was pulling on the sensor (still mounted) and i could control the rpms to a certain degree (you should not be able to do that ) so i figured cheap aftermarket tps sensor = crap ....next i'll be buying a motorcraft unit .

 

[redrocket1468]

i appreciate the suggestions i will take a look at it soon and report back when i have an answer

thanks