Ok, I have a cylinder 4 misfire and also sometimes a 2. I did already get the left cylinder head replaced under the warranty but it has come back and they even double checked everything and claim it looks good. It also has coil packs which are less than 6 months old and spark plugs that are now brand new. I was more or less curious if anyone else has had this issue and has any ideas? I plan on tracing the wire harness and looking for any obvious frays in the wires, if anyone has a part number for the wire harness I might need or tips on the wiring that goes to the left head that would be helpful. Also plan on taking a look at the injectors however, I do not think that is the issue since there are no other symptoms of that. It is intermittent so when I went to the dealer they claim they couldn't get it to come back on (even though it came back maybe 2 hours of drive time after I left) then charged me to replace the right side spark plugs which were all a year old. Needless to say I won't go back there. Please let me know if any of you have any ideas or similar issues or mostly tips on the wiring harness that goes to the left head as this is what I am really leaning towards. Thanks!!!