I have a 01 rado with the 4.8. My service engine soon light blinks when i get the truck over 4000 rpms, then once it gets below 4000 it shuts off. Then last friday pulling my racecar i brought it up over 4000 rpms it started blinking then it stayed on. I have a cortex programer, so i checked the dtc's and it told me i had a misfire on number 3 cylinder. It does it when i'm not pulling the racecar also. Can you guys help me?