The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - Possible Quadrajet issue....surging at WOT...vacuum leak?

Dead Parrot · 09-14-2019, 10:43 PM

Might double check the intake bolts for tightness.
A brake booster can leak enough to mess with the idle and still be effective at braking.
Check the suction side of the fuel lines. Bad rubber lines tank to frame and frame to pump can let air into the system. A small leak can cause your WOT symptoms.

2nd on checking the high idle screw(opposite side from the normal screw).
Also possible that the linkage isn't letting it fall to the low idle side. Lots of variations on how that works depending on the type of choke.

Yes, if everything is working, backing the main idle screw out enough should kill the engine.

09-14-2019, 10:43 PM	#4
Dead Parrot Registered User Join Date: Aug 2012 Location: Oklahoma City, OK Posts: 2,482	Re: Possible Quadrajet issue....surging at WOT...vacuum leak? Might double check the intake bolts for tightness. A brake booster can leak enough to mess with the idle and still be effective at braking. Check the suction side of the fuel lines. Bad rubber lines tank to frame and frame to pump can let air into the system. A small leak can cause your WOT symptoms. 2nd on checking the high idle screw(opposite side from the normal screw). Also possible that the linkage isn't letting it fall to the low idle side. Lots of variations on how that works depending on the type of choke. Yes, if everything is working, backing the main idle screw out enough should kill the engine.