ZR-1 Net Registry Forums - View Single Post - Fast Idle on 91 ZR-1

Anonymous · 12-14-2003

Would appreciate opinions on what to do/where to look for this problem:My 91 ZR-1 has been idling a bit high lately. The real annoying part is when you're slowing down and push the clutch in and the idle goes to 1500 rpm. When sitting for at least 15 seconds, the idle goes down to about 1000 rpm but it takes awhile. The car wants to run at 1500 rpm all the time once in motion, coming to a stop and when pushing the clutch in. Additionally, my gas mileage has gone to h*ll
.Other than the idle, the car runs fine. Any ideas on where to look or what to do to fix the problem? I couldn't find anything in the Chevy service manual about adjusting the idle on a ZR-1. On a tuned port or LT-1, you can start the car, disconnect the IAC plug-in, and then adjust the throttle/idle screw. I tried that on the ZR-1 and backed the throttle screw out all the way. That got me from 1200 rpm down to 1000 rpm but it's still idling too fast and wanting to operate at a higher rpm once moving.

12-14-2003	#1
Anonymous Join Date: Dec 2003 Location: Grand Blanc, MI Posts: 491	Fast Idle on 91 ZR-1 Would appreciate opinions on what to do/where to look for this problem:My 91 ZR-1 has been idling a bit high lately. The real annoying part is when you're slowing down and push the clutch in and the idle goes to 1500 rpm. When sitting for at least 15 seconds, the idle goes down to about 1000 rpm but it takes awhile. The car wants to run at 1500 rpm all the time once in motion, coming to a stop and when pushing the clutch in. Additionally, my gas mileage has gone to h*ll .Other than the idle, the car runs fine. Any ideas on where to look or what to do to fix the problem? I couldn't find anything in the Chevy service manual about adjusting the idle on a ZR-1. On a tuned port or LT-1, you can start the car, disconnect the IAC plug-in, and then adjust the throttle/idle screw. I tried that on the ZR-1 and backed the throttle screw out all the way. That got me from 1200 rpm down to 1000 rpm but it's still idling too fast and wanting to operate at a higher rpm once moving.