Engine Performance problem
1966 Mercury Comet V8 Two Wheel Drive Automatic 67,070 miles
just had shop put in rebuilt C4 tranny. Idle spd was too high, and tranny shifted hard. When I drive it short distances I have no problems. Its when I drive more than 4miles, or on freeway that stalling begins. My car stumbles and acts like its not getting enough fuel. If I try pumping gas pedal, it cuts out. Stalls motor. If I let off gas pedal it stays running at slower and slower rate, until attempts to maintain speed cause it to stall. What I have tried so far has failed to stop this behavior. This is what I have done so far. 1)adjusted choke cold idle spd down, adjusted both air/fuel screws one full turn out past " bog" point. So now car idles nornally, and shifts smoother also. 2)replaced air & fuel filters, added gas treatment. 3)checked fluid levels. Stalling behavior pursists.
From what you describe, I would take a fuel pressure test, meaning flow as well as pressure. Then go into distributor and check breaker plate for wear and vacuum advance for wear at pin and pin hole. I am assuming this has the original distributor with points. It could also need a carb overhaul as well, due to age and the alcohol in todays fuel. Especially if this has a plastic float in the carb.