The truck has been back in the shop again, this time because of chugging and hesitating when decelerating from highway speed. I was hoping it would be traced back to another rodent chewing the wires, but that's really stopped since a neighbor put out rat poison, because something was chewing the wires in his Hummer. No such luck though, this time the spark plugs and ignition coils were bad. Six...SIX!!...plugs broke off in the cylinders when they tried to remove them, which meant a lot more work to finish the job, which finally cost $1073. Seems fine now.