If you can screw the idle jets all the way in without stalling the car, then you have an internal gas leak in the carb. Seeing that a vacuum leak allows more air into the intake system, leaning the carb by running the screws in, should make it quit idling sooner, instead of later. Either way, a car shouldn't idle with the screws all the way in, which makes me think that something has gone wrong in the carbureator. ----- Original Message ----- From: "KerryPinkerton" <pinkertonk@xxxxxxxxx> To: "IML" <mailing-list@xxxxxxxxxxxxxxxx> Sent: Friday, March 15, 2002 6:16 PM Subject: IML: 440 vac leak?? > > Now for the interesting stuff, under some conditions > of timing, I can screw the idle jets all the way in > and the car still runs which makes me think vacuum > leak. Also the car will not idle down below about 600 > RPM even with the screw completly backed out. >