ChuckV
Seems that we are driving the same car! Interesting that we have the same problem although different model years. When I ask other CMax owners around town they never have been bothered by a p0340 error.
Bob, my CMax mechanic, called the Ford repair folks in Dearborn but they were not much help. He suggested trying more frequent oil change in winter which I did. So far no p0340 error.
Did your mechanic have any suggestions?
BTW what part of the US do you live in? I'm in upper Midwest.