ok here is my issues..i got a 02 z28 that i have replaced the ignition lock cylinder whcih is what all my trouble shooting has pointed to but what my problems are is this...if i leave the car alone and go crank it it will run at 10 min exactly doesnt miss run funny or anything its as strong as ever but it shuts its self off...on occasion it wont crank back it has fuel pressure but no fire and it differs on run times sometimes it will run for 10min fine then just die and then fire it back up and it will run for a few seconds then dead again any info on what i could do to fix this??