I have a 92 Sho. Sometimes when I stop at a light or something, the rpms will dip to 600, then to 400, then stall, but then I can start it right back up again and it idles fine. If it starts to dip, and i rev the engine, it stops stumbling. This makes me confident its not the Cam or Crankshaft sensor because it kicks right over again with no problem. So is there anything that would cause this intermittent stumble/sometimes stalling problem. And by the way, the A/C is not on when this happens, partially because when I turn it on I hear slippage, and if i turn it off the slippage stops. So, sorry for the long post, but any ideas?