Have developed a rough idle on my 80 Vette. Changed the carb to intake gasket last week-end, but did not cure problem. Car runs fine cruising down the road, but at a stop light, I have to put it in neutral to keep it running. Problem seems to come and go. Car has only 19000 mi. on it. Sounds like a vaccum leak somewhere, but can't find it.

Your car has a lot of miles on it. Probaly every hose needs to be replaced.Put the carb on fast idel and spray some choke cleaner on everything-when the engine speed picks up you found the vacuum leak!
Steve

Steve said: Your car has a lot of miles on it. Probaly every hose needs to be replaced.Put the carb on fast idel and spray some choke cleaner on everything-when the engine speed picks up you found the vacuum leak! Steve

or if you have oxy acetylene tanks turn the oxygen on ONLY.. and move the head near an area you suspect a vaccum leak.. when it sucks in pure oxygen the engine will rev..

i would take all the vacuum hoses off the engine and plug everything.. then add things on one by one until you find the leak..

All of the suggestions sound cool, but do the easy thing first and isolate the vacuum system from the rest of the car. Just plug off the vacuum port(s) from the intake and see if the idle returns ok. This leaky situation causes a lean condition in the rear two cylinders and make a rough running baby. Had the same problem on mine and most likely it will be in the headlight circuit. ( 80's have vac lights? ). Had to eventually replace everything, as the vacuum leaked a tiny bit from everywhere and added up to one big one. Expensive repair, but she ran great again till I decided to fix the horn and eventually the fatal restoration vortex swallowed me. Good luck....it can be done.

Thank's for the imput guy's. Will try your suggestions this week-end and hopefully find the problem
| (19000 mi.not 190000 mi.)

Found the vaccum leak Replaced the EGR valve gaskets and everything is fine. Thank' for the imput guys