Idle Problems Need Help!!!!!!!!
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Joined: Feb 2008
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Idle Problems Need Help!!!!!!!!
Hello all I am new to the Vette scene and wanted to ask a question I just purchased a 81 with 79K miles and I continue to have idle problems. The car had been sitting since 89 so I replaced all vacuum lines due to dry rot this seem to help some but still continued so I had the carb rebuilt and did check the Throttle Positioning Valve also and it seemed to check out all right just re-installed it and again runs better but still have rough idle it wants to vary from 6-9 hundred rpm and starts loping any suggestions????????? Any help will be greatly appreciated.
Jesse
Jesse
Melting Slicks
Joined: Aug 2005
Posts: 2,359
Likes: 15
From: Confusion
What about the intake seals, head to intake? Take a box wrench and check the intake bolts, if they are loose tighten them and see what happens. My 69n BB had a loopy idle and I found every bolt was loose, took almost whole turns to tighten, and it did level off the idle. Make sure to tighten in the correct numeric pattern..............B
Worst case scenario, yank the intake and reseal............
Worst case scenario, yank the intake and reseal............
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,116
From: Crossville TN
Check manifold vacuum level at idle. Your engine should show something around 20 in. Hg. if it is in good condition. If you find it to be much lower than that, resolve the manifold "leakage" problems first. The bad idle condition may just be a symptom of an associated issue [rather than just isolated to the carb].
Drifting
Joined: May 2006
Posts: 1,480
Likes: 2
From: Circleville Ohio
Vader Vette
Hey didnt they use to spray starting fluid around the base of the intake manifold and if it has a leak it will rev up higher (and yes that stuff is highly flamable)that problem sounds like what was happening to my vortec v-6 but it turned out to be the fuel injector rail put in a new rail and the darn thing idles great. I know you said carb. It does kinda sound like an air problem.Kinda sounds like the computer might need re-programmed if it has one. not sure.
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Joined: Feb 2008
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Tks I have done the spray with no success of finding a leak also I have replaced the brake booster it seem to be worst when pushing on the brakes but again no luck. How do you reprogram the computer? I know that there is a hookup under the ash tray is something that can be checked for codes and could Autozone? Any other ideas??/
Tks
Jesse
Tks
Jesse
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Joined: Feb 2008
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Well worked on my idle problem again yesterday and I think I have got it. The vacuum sensor that is in the thermostat housing was not opening the damper valve on the exhaust once I bypassed it and drove it the computer adjusted itself and she seems to be purring now. Tks for all the help. 
Jesse
Jesse
