ZR-1 Net Registry Forums - View Single Post - 90 ZR-1s and fast idling?

Aurora40 · 07-27-2008

My car has only done that when it had leaks. When I bought it, it already had the latest PROM, and I've had Haibeck PROMs since. Mine only idles high when the car is moving, like when slowing to a stop in neutral it will idle around 1000-1200, but drops when the car stops.

If you can scan it, look at what the "desired idle" is and also if the IAC counts come down when you stop. If so, but the idle doesn't drop, it's a vacuum leak. If it doesn't command it down, perhaps you need an updated PROM.

07-27-2008	#4
Aurora40 Join Date: May 2005 Location: Leesburg, VA Posts: 2,704	Re: 90 ZR-1s and fast idling? My car has only done that when it had leaks. When I bought it, it already had the latest PROM, and I've had Haibeck PROMs since. Mine only idles high when the car is moving, like when slowing to a stop in neutral it will idle around 1000-1200, but drops when the car stops. If you can scan it, look at what the "desired idle" is and also if the IAC counts come down when you stop. If so, but the idle doesn't drop, it's a vacuum leak. If it doesn't command it down, perhaps you need an updated PROM.