This problem has been happening before my 60K service. At that time, the fuel filter was replaced. They did both a compression test and leakage test. I'm really thinking this is more of a fuel or ignition related problem, as it seems to be related to outside temp/humidity and not enginer temp. My dealer's scope is out, so I'll definitely find someplace else that has one. Not sure it matters, but it's more of a occasional miss than anything else.