I have a 1986 Ford Bronco II 2.9 auto. The problem is when accelerating I have to accelerate slowly. As long as I push the pedal slowly I can get up to 65 or 70 mph, but if I push hard at all it has a dead spot. Pushing harder just makes it worse. It doesn't just do it on take off, if I am cruising at 45 mph and want to be at 55 mph, I have to do it slowly, and not push too hard. I have changed throttle positioning sensor, EGR valve, fuel pressure regulator, coolant temp sensor, map sensor, oxygen sensor, fuel filter, and rear fuel pump, new tune up, plugs, wires, and distributer cap. Any ideas? Thanks in advance.