Thread: idle waaaay too high.

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i took my 82 350, with hei and a quadrajet, for a light break-in cruise last night and it ran fine, except for an off-idle stumble once it warmed up. got home, shut it down, went to bed, and didn't adjust anything on the truck. tonight, i started it up, and it is revving insanely high. i was not about to put it in gear revving like that. i rummaged and found no vac lines loose, and the intake manifold seems to be sealing well. before i spend tomorrow's few after-work daylight hours hunting, does anyone have a suggestion?

the choke was one of the first things i checked. linkage is adjusted fine.

the fact that i can cup my hand over the whole carb, primaries and secondaries, and the idle does not change bugs me. i do not know how a vacuum leak of that size could develop overnight without the vehicle even being touched. weird.

Sounds like the secondaries are sticking. Try loosening,then retightening the four carb holddown bolts. If one is too tight, it can twist the carb enough to cause this.

Any chance the throttle rod is catching on something and not allowing the carb to return to idle?

nope, i've checked those things. secondaries move properly, throttle moves smoothly. no vac lines disconnected. i certainly want it to be something along those lines, though. something like a leaky manifold is a much bigger pain. i'll give it all a better look when i have some daylight.

thanks

out of curiousity, how many vac lines are NEEDED to run a quadrajet? i know a lot of that mess is purely emissions control garbage.

maybe when i get home from work i can snap a few digital shots.

http://streetmachinesoftablerock.com...opic.php?t=350

Turn it on and maybe try spraying some wd-40 around the intake area see if rpms change.Pay attention to what you spray when rpms change.If you do this, use a plastic bottle sprayer.If you hit a power lead with a metal can you can blow you hand off!!!!AND DON'T SIT THE CAN ON THE BATTERY!!!!!!!You can also use a soapy solution also.

i used propane to check, like i used to on my old honda. nothing. i just really find it strange that it was fine when i shut it down wednesday night, and totally messed up 24 hours later, without me touching a thing. i don't think i'll be off work in time to mess with it, today, but i have all tomorrow to mumble profanities at it.