Crap! I have a bizarre engine problem that I can't fix (yet). I have all the signs of a horrible vacuum leak... stalls at idle, runs very rough at low RPM's, etc., but I can't find a leak. But then I also feel an occasional miss at high speeds too. My fuel pump works, my filter is new, my timing is fine. My highway mileage hasn't changed either. I removed the carb (edelbrock 1405), and found the bowls coated with gunk (mexican fuel is my guess)... I thoroughly cleaned the guts with solvent and compressed air, and I checked the action of the floats. I reinstalled the carb... no difference. I replaced the coil and plugs... no difference. What's up?! Any help is appreciated.