replaced: fuel pump, sensors, cleaned screens on sensors - still, when i drive it for about 15 minutes (enough time to warm the car up good) it does this 'jump' thing, like mini missing - the service engine light comes on, then it will die within a few minutes. i put it in park, it starts right up, no 'lite' on and it drives okay for a few more minutes, any suggestions what is wrong? we have changed the EGR valve, tightened whatever was loose, don't know what else to do..need help!