Hi everyone, I have a weird problem with my 84 chevy camaro. Every once in a while when I come to a stop when the cars warm, it'll idle low, like 400 rpm or lower. But if I put it in neutral and back into drive it'll go back to idling at 500. Also while idling low it has no takeoff power, seems sluggish. I cant tell if it's an engine or transmission problem. Timing is set to 15 initial 35 total. Carburetor is a holley 750 vacuum secondary (has the adapter plate for the square bore. And the bracket to work with the 700r4). I've found and fixed vacuum leaks and it didn't help with this particular problem, but runs much better. Any help would be appreciated.

Edit: I forgot to say that I have already changed the distributor to a vacuum advance unit (hooked to ported).

 

I would try a manifold vacuum source for the advance. And 15 deg. advance is pretty much for a stock cam engine.

 

Sorry I forgot to say that the engine is stock with stock cam. It really likes 15 initial. I've tried manifold and it will idle higher like about 600 in drive but it will still drop to below 400 when coming to a stop. And it takes off all doggy. When I put it in neutral and back into drive, if I floor it, it'll spin the tires all the way through first. Its crazy to me, like no matter what I do to the tune or the timing it still does it. Thats what makes me think maybe it's a tranny problem?