Rubicon04

I've been a Jeep enthusiast since 1997. My first Jeep was a 1982 CJ8 Scrambler. One YJ and 4 TJs, the current one being a 2004 Rubicon with 52,000 original miles and trail modified. I have been experiencing the famous P0301 trouble code very intermittently unless it was cold outside, then it was steady. Rain or shine didn't seem to change anything. I live in Minnesota where winters are cold. Started with the obvious tune-up, copper plugs and the coil rail. Battery connections, grounds, injector cleaning and replacement, throttle body cleaning. The works. Could not isolate the