I just had my coronet running great, would idle nice n smooth and start right up. Yesterday I was driving around when I came to a stop and the idle was real rough and it died, restarted and drove fine when you stay on the gas but now soon as I get off the gas she dies. Has brand new fuel system (tank, sending unit, pump) New electrics (coil, wires, plugs), Just cleaned out carb real good. Im thinking maybe vacuum leak somewhere, whats a good way to check for this?

 

When I cover the carb intake hole slightly, the idle raises, indicate a vac leak?

 

yeah, Check all the vacuum lines for cracks or loose fittings.Power brakes?: booster bad,Vacuum advance on distributor?: bad diaphragm, Bad PCV valve? Choke adjustment?

You can use silicone spray around the intake manifold to see if changes the RPM's.

If you have a vacuum guage,hook it up to manifold vacuum and see what it is.

Just take your time and check everything, good luck, john

 

ok so went and checked all vacuum lines and put new gaskets in the carb., pvc valve is good, no power brakes, vac. advance on dist. brand new, works, choke adjusted correctly, seems to be running good again after the gasket change in carb.

 

Yes, those gaskets tend to dry rot and crack with age just like me!

john