The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post

tucsonjwt · 09-16-2011, 10:03 PM

My guess is it is doing nothing now. So, I think it is designed to sense when the A/C is on and activate the fast idle solenoid to compensate for the drag on the engine when the compressor is on. On my 83, everything is hooked up properly - my relay is attached to the valve cover of my 454, but the idle does not pick up when the A/C is on. This does cause the engine to barely idle at a stop light, but the engine does not stall, so I don't mind. Sometimes I will rev the engine a little at idle if the engine starts to lope. I think the solenoid adjustment screw it is attached to is turned out all the way, so not engaging the throttle. I prefer not to have a fast idle and waste gas.
Bottom line, disconnect the wire to the A/C and see what happens. You can always turn the idle adjustment screw on the carb to get a higher idle during the summer when you are running the A/C - you will just burn more gas when the A/C is not running.

09-16-2011, 10:03 PM	#4
tucsonjwt Registered User Join Date: Jul 2007 Location: Tucson, AZ Posts: 3,188	Re: Still trying to figure out this box My guess is it is doing nothing now. So, I think it is designed to sense when the A/C is on and activate the fast idle solenoid to compensate for the drag on the engine when the compressor is on. On my 83, everything is hooked up properly - my relay is attached to the valve cover of my 454, but the idle does not pick up when the A/C is on. This does cause the engine to barely idle at a stop light, but the engine does not stall, so I don't mind. Sometimes I will rev the engine a little at idle if the engine starts to lope. I think the solenoid adjustment screw it is attached to is turned out all the way, so not engaging the throttle. I prefer not to have a fast idle and waste gas. Bottom line, disconnect the wire to the A/C and see what happens. You can always turn the idle adjustment screw on the carb to get a higher idle during the summer when you are running the A/C - you will just burn more gas when the A/C is not running.