I have a 07 Ram 1500 Quad Cab 5.7L Hemi 4x4 TRX4 that has a misfire on cylinder 1. When I start it, it will idle rough then when I start to drive it will clank (misfire) for about 1-2 miles then smooth out and run fine for the rest of the day. I can then turn it off and restart it and it will not misfire. Some days it will misfire and other days it won't. I've tried replacing all the spark plugs and the coil on cylinder 1, switching spark plug wires, switching plugs and wires and coils to other cylinders, checked compression, switched injectors and checked injector wiring, smoked the engine for vacuum leaks-none, pulled L. valve cover checked valves and springs, and switched deactivation solenoids. It still misfired on cylinder 1. Then I brought it to a Chrysler dealership and they updated the computer. I drove it for about 75 miles and it started misfiring again on cylinder 1. Does anyone have any idea what I can try next?