My 2002 GP (3.1 SE) behaves strange, it lacks of power. It seems that out of
175 hp I have only 75 left, It has only 2000 rpm when I am driving 70mph, and sometimes goes down to 1800 without gear changing. Sometimes when I press the acc. pedal engine is slowing down. What could it be? I thought it was bad fuel, but problem persists after new filling.