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I was wondering if anyone on here has had any issues with their throttle bodies causing a high idle. After tons of investigating and a trip to the shop I am thinking my actual throttle body is wore out. It doesn't seem to want to allow everything to rotate back all the way causing an increase of roughly 500 rpm. I can manually pull the rotator back and the car will idle down (800 rpm) but it won't do it on it's own (idling at ~1200-1500). I have the screw backed out so I know it's not hitting on that. The motor had roughly 300,000 miles on it when it was given to me before I rebuilt it, so could the tension springs just be shot? I'm thinking maybe just swap it out with a lower mileage throttle body. Anybody have any similar experiences?

what screw do you have backed out?

the throttle screw in the body (down in that hole) is a factory set screw and shouldn't really need to be touched if everything is in working order. Stock position is about 3 turns out from the bottom.

If the butterfly isn't going all the way back, make sure your TB isn't all gunked up, just pull off your intake and look inside. should be aluminum, not gunk.

If its clean, check to make sure its not hitting the throttle stop. That is a little screw that the throttle linkage hits at closed throttle.

then check your throttle return springs. may have broken/fallen out/weak. also make sure the cable isn't sticking or anything else isn't preventing it from returning.

I have not touched the set screw. I am referring to the throttle stop. Everything appears to be good. Inside is pretty clean. Mainly aluminum with small traces of carbon. My springs are still in tact but I'm thinking they are probably just wore out. Do they make a rebuild kit or is it easier just to find a replacement throttle body?

KLDE? replacenment TB is probably way easier. I wouldn't pay more than $20 from a pick-n-pull.

Or on here or PT.

But try disconnecting the throttle cable from the linkage and pull/push it by hand and see if it sticks. IIRC, there is a return spring on the pedal too.

You should also find in the manuals the suggested slack. It should be quite loose at 0 throttle. I've made that mistake before, making it a bit too tight.

I've done it on a few, wound the spring an extra rotation on the TB to retension it, takes a second set of hands however..

Okay thanks guys I'll give those suggestions a try.

Had some time to get back to the garage today and it seams it must be the springs. Loosened the throttle cable and disconnected it and it didn't change anything. Guess I'll have to start looking for a low mileage throttle body.