Looking for an old thread, it was a while ago who knows where it's at: I have the identicle problem. Car misfires only at idle (not a rough idle) and runs great off idle. I still have the problem even after a fresh rebuild, so it would have to be electrical or vacuum. I read the old thread which it suggested adding an extra ground to I think the ignigtor? ( I'm not sure), that seemed to solved the o.p.'s problem, too bad I can't find it, it had a nice illustration. Where was that thread or can someone suggest another solution or what could it be?. Thanks!