1990 GW, runs, stutters, recovers
135K on vehicle, 80K on second engine. Professional rebuilt carb, new fuel filter, new air filter, new plugs, wires. Going down the road all is fine, then all of a sudden it feels like no power to the wheels, engine is still going, will either kick back in or blow black smoke, backfire, cut out. My mechanic described it as "gas piling in," but he was only guessing. Stumped and confused, need help please!