I have a 2000 F-150 4x4 5.4L, and it has a serious problem. It is missing on one or more cylinders. Unfortunately the problem started 800 Km from home on the holiday weekend after driving through a LOT of rain. I had no choice but to limp it home on 7 cylinders. About 50 Km into the road home, the day after the rain is when it started, and sonn after the SES light came on. Twice as I was driving, the truck shut down completely, and both times the odometer changed from numbers to a line straight across(pcm maybe?). Transmission is also acting strange, OD not usable in this condition, but sometimes going up hills in drive, it would shift itself into neutral. Whenever this occured the OD light would go out and need to be locked out again. After I got home, I diagnosed the number 8 cyinder as dead by removing the plug form the coil on each cylinder, and not finding any noticeable change in idle or performance on only #8(unfortunately can't reach #4 without removing parts). This was also my first long trip with my truck which has the Holley Thunder supercharger kit, but for two years has run fine. I realize the coils are subject to failure in moist conditions, but does anyone know if the computer will isolate a coil and shut it down if it detects a problem with the cylinder? I also have a set of edelbrock shorty headers that I installed last month, and now the header noise seems to be louder. Can anyone tell me if it is just the coil, or if maybe it could be a fault in the PCM? My work schedule prohibits me from going to a garage, and both dealerships can't even look at for about ten days. Any help will be appreciated.