rpm's hang, cant solve problem!

Econolodged · 07-20-2006

hey, i have an 89 coupe 5.0 5 spd. only mod on motor is underdrive pulleys. at least once a day itll idle at about 1100, and say i rev it out to 3 and take my foot off itll hang there for a bit before it backs off. its driving me up the wall i dont know what it is and nobody seems to know. does anyone else have this problem? any ideas? i would greatly appreciate any feedback.
Josh

1970Mustang351c · 07-20-2006

That happens to me also but once the car warms up the problem seems to go away. I dont know what it is though.

Young_Buck · 07-20-2006

I'm trying to decipher this..

So... when your running you car (Hot or Cold?) and you press the Accelerator down and run it, then come to a stop or depress the clutch pedal, the idle will hang up at about 3000 RPM (For how long?) then drop down to the normal idle?

Is that correct?

-YB

GhostDog 5.0 · 07-20-2006

I would clean the throttle body out really good and give the maf a good spray with electronic contact cleaner. Also hose down the idle air control valve with carburetor cleaner or throttlebody cleaner.

93superstang · 07-20-2006

i also have a 89 gt 5.0 5 speed and that same problem started to happen to me, but i would have to shut the car off to get the rpms down. my solution was to change the injector harness out. took me about 1 hour.

Econolodged · 07-21-2006

hey, sorry if i wasnt clear. it doesnt matter if the car is hot or cold its pretty random. when its doing it it doesnt matter what rpm i run it to i just used 3 as an example itll hang there for a few seconds then drop down to 1100. for some reason when it does this it always idles 1100. if i keep driving it or leave it be itll go after a while but it does it at least once a day. its pretty annoying. and ghost dog i did that last summer and it really seemed to solve the problem but it came back this summer. i store my car for the winters because i live in canada and its never seen snow yet. so it hasnt had many miles on it since then. do you think it would need it again already? or would it be something else?

Econolodged · 07-22-2006

hey, i dunno if this will help you figure it out but when my car was running fine i was poking around the back of my motor where the pcv is and i dont know what exactly my hand hit but it jumped right to 1100 rpm and was all ****** up again. thanks.