I have a 2004 Jeep Grand Cherokee 4.7L nonHO. I get a P0308 code that I have not been able to hunt down. It is odd because I only get the code if I restart the vehicle when it is warm. If I let it cool down all the way, no code, but if I restart after an hour or so, the code pops up. I have changed the plugs and the coil. I have run injector cleaner, but not changed the injector as I am nervous about busting the tiny plastic clips with my big meaty paws. Any ideas would be appreciated.
Kinda sounds like a leaky injector giving a too-rich condition on a hot start. Did that plug look any different than the others?