Engine starts. While pressing accelerator, truck stalls.

[kreppnar]

My 1988 Bronco 2 XLT, 2.9L 4x4 Automatic, is having a problem with the acceleration. I can get the truck to start up, but when i press the gas, it sounds like it sucks in a bunch of air and not enough gas, so the RPM gauge shoots down to almost 0. When i release the pedal, the RPM's go up to about 2 to 3k. Then it goes back down until i press the gas pedal really quick. Then it will rev up again. It has two new fuel pumps, and it's getting good gas pressure. Ive replaced the following parts so far.

Boith Tank and Frame Fuel Pumps

Throttle Positioning Sensor

Air Bypass Valve

Fuel Filter

Distributor cap, and rotor

Spark plug wires, and sparkplugs

Starter

Solenoid

and Pos battery cable

Ive cleaned out the throttle body, and ive checked for air leaks in hoses. I noticed that when i do press the accelerator, the suction from the fuel injector unit, sucks so hard it sucks in the side wall of the air filter box. I was told to check the MAP sensor, and so i have taken it out, to get it replaced. I dont know what else to do. This all started after it had stalled at a stop light and the solenoid and battery cable (POS) were VERY hot and melting. Those do not get hot anymore.

[tekatlarge]

Could possibly be a fuel pressure regulator gone bad. It might be it is diverting so much fuel back to the tank that you don't have enough pressure to maintain the demand of the injectors. Slap a fuel pressure gauge on it and see what you have. Also pull the vacuum line off the regulator and look for signs of fuel in the vacuum hose.