Every time I start my Jeep it dies at least once. Sometimes it will even die while I'm driving but will usually come back if I pump the gas pedal. The mechanic said I needed new fuel injector o-rings, so I changed them and nothing changed. Then he said to check the vacuum hoses to see if any where damaged, which I did and their all fine. I thought it could be the fuel pump but doesn't the check engine light come on with that problem? We also put a computer on it and it said I need a new oil pressure sensor and temperature sensor. Would those not working cause it to die?