I'm new to the diesel world also. just recently bought a 03 F-350 with 7.3 with 164k miles on it. the problem that i am having is that every once in a while the check engine light will come on, but when i run the code reader on it, it passes. but as soon as i shut the truck off and start it back up the light turns off. but thats not all it also kills on me when im coming to a stop not all the time but it did it twice to me today. but it starts right back up once i put it in nuetral and crank it. it also, not surges but jerks sometimes when i driving, like its missin a beat or something. but all this doesnt happen very often. also the ignition still beeps when i take the key out the ignition when i get out the truck i have to play with it to get it to stop beeping. i was thinking bout gettin the oils changed(motor and tranny) to see if made a diff but someone told me that maybe the ignition could be causing a short to make the check engine light come on and maybe the short could be the reason for the shut offs and the jerking like it would be tellin the computer that the key is in the off position but its not. id rather replace something small b4 goin into the tranny. i was reading some of the threads about the cps and other things but i dont think its those things. Please help with any suggestions.