My problem started in late June or early July when I stopped at 7-11 to pick up a drink. Turned the truck off, went into 7-11, came out & started the truck. When I came out and started it back up, the truck started surging/misfiring when driving & you could feel the surging/misfiring pulse through the brake pedal when stopped. After 1 block of it acting like this, the CEL came on. I took the truck to have the codes checked the next day, and it was determined to be a bad #4 spark plug. So we changed all 8 plugs and wires (Mototcraft Double Platinum plugs & Motorcraft 8 gauge wires). The CEL turned off after this and has not turned back on, but the truck now lacked power. Between then and now, I have had 5 different shops check the truck out (2 Ford Dealer & 2 Independent shops & 1 AAMCO). None of them could find the problem, even though one shop stated it was the IAC & FPR. So since it all started I've replaced: IAC, FPR, EGR, TPS, all 4 02's, 8 plugs & wires, PCV & Fuel Filter (ALL Motorcraft or Ford parts). Both Ford & myself cleaned the MAS/MAF, and Ford ReCalibrated the PCM. Each item seemed to give the truck back a slight amount of power, but nothing drastic. This is when my problem started. How the transmission would be affected when I have a #4 spark go bad, I don't know.
Any thoughts?