My trooper has had this problem for a long time, it always hesitates when you hit the gas pedal. It takes about 1 sec to respond to the opening of the throttle. When the engine is started in the morning or when the engine is cold and you hit the gas pedal, it backfires from the intake with a loud pop sound. I have changed all the sensors inthe car except the TPS, and yet it still happens on this particular car. Does anyone have a clue as to what could be the problem? Also i am thinking, could it be the cooling fan? cos the cluch went bad and a made the clutch fixed, so the fan rotates as fast as the engine.
JM
JM