I have a 1999 Gmc Sierra 4x4, ex cab, reg bed, with 170000 miles. The truck will turn over and run for about a second or two. If you try to press the gas pedal in that time it will die right away. I have tried a tune up that didnt work and then i tried changeing the fuel pump and it still does the same thing. It has been in Colorado its entire life. Can anyone help me with my truck? Since my post the other day i have changed the fuel filter and tried my old mass air flow sensor to see if that is my problem. The weather has been very nice and mild ever since my truck stoped working on 2/7/09. Well it still didnt work. and it was suggested to me to change my cap and rotor but this engine does not have those it is a coil over set up. Any other suggestions would be helpful.