1992 CHEVY 1500k series

Truck will only start when gas pedal is to the floor. But will stall out when pedal is released. Changed fuel pump, fuel filter, spark plugs, ignition module, COMPLIED WITH CHECKS on the O2 sensor, Throttle Position sensor, MAP sensor, idle air control valve. I did remove the throttle position sensor out of the throttle body and removed the connector from it also. My truck started fine, it reved up fine, when I took it out of park it stalled. I am lost. Any answers