88 Crazy High Idle Problem! PLEASE Help!
Thread Starter
Racer
Joined: Oct 2004
Posts: 409
Likes: 2
From: Toronto Ontario
88 Crazy High Idle Problem! PLEASE Help!
New iac;new egr valve;vacuum looks good, no visual leaks; removed 52mm throttle body and cleaned, opens/closes OK; correct TPS sensor reading; throttle cables look good, -no binding. Starts and idles OK at 800 rpm, but once I depress the gas all hell breaks loose. Idle jumps up to 1300 and stays there, when driving it's like having cruise control on, the damn thing sticks at 1300-1600 rpm enough to keep the car moving well. The only way to bring the rpm's back to normal is with a quick depress of the gas pedal. It's like the throttle's getting stuck, but strangely the throttle body is closed and resting against the adjustment screw then it happens. Had code 32, fixed it with new egr valve and now no more error codes reporting. I'm thinking it might be the ECM, could it be bad? but before I get one I though I'd ask if anyone had a clue as to what's going on with my car.
Thread Starter
Racer
Joined: Oct 2004
Posts: 409
Likes: 2
From: Toronto Ontario
TB was no good. when I swapped it with the original the problem was gone. I could feel a little bit of play within the shaft of the no good TB, but I didn't think it would of made that much of a problem. Does anyone know what the allowable tolerance is between the shaft and the bushings? What about the bore and the plate? 
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Since the throttle is resting against the stop screw, the only way air could be getting in at the TB is if the bushings are worn and leaking in air.
A scan tool would tell you if the ECM is calling for high idle or trying to lower the idle.
A scan tool would tell you if the ECM is calling for high idle or trying to lower the idle.
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