Questions and Answers

Cherokee Fuel Pump Problem? Q. Dear Vince, I have a 1989 Jeep Cherokee 4.0 liter 6cylinder MPFI. When the engine is cold it takes a lot of cranking for it to start. When its hot, it fires up normal. Also my fuel pump hums loud after an hour or so of driving. Could this be a cause or maybe loss of intake manifold pressure?

A. A bad fuel pump could explain both problems. When you go out to start the car in the morning, turn the key to the ON position but do not start it. Wait about five seconds (or when you hear the fuel pump shut off) then turn the key OFF. do this four or five times then try to start it. If it starts right up then you have a fuel problem.