I have a 1964 Pontiac Starchief with a 389 i recently put on a 4 barrel manifold and a new edelbrock 600cfm carb (electric choke). When i finally get it to start it idles extremely rough idling high then low then it eventually just gets reving high and stays there. If i hit the throttle it idles erratic again then revs high. I thought it was a vaccum leak and sprayed choke cleaned around all the gaskets it did not change the idle indicating a vaccum leak. I then replaced all vaccum hoses, the pcv valve with the grommet was replaced as well (pcv valve is located on the crankcase behind the intake manifold). I then took the vaccum hose off from the break booster thinking it was a leak inside it and caped the hose off and still no change. The engine was doing this before i even replaced the carb and intake manifold so im running out of ideas. Please help.
May 17, 2010 at 7:25 PM