As I was pulling out the dreaded check engine light came on and started flashing, along with rough running. They were closed, and I only live a few miles away so I went on home. Pulled the P-0301 code, cyl1 misfire, so I started looking things over and pulled #1 plug. Looked OK, but it's a NGK R plug. Seems I remember that these 3.7's don't like expensive plugs very much, so I guess a set of plugs is in my future.