This weekend I was towing my boat to the river and experienced a issue. It seemed to happen more when climbing a hill, but did do it on flat too. It would surge and I was able to notice the RPM's drop then come right back up. It did this once or twice during the first hour of the trip then did it 3-4 times almost in a row and after that the CES light came on. Also after that I put the tuner back to stock (DP-Tuner) was on the 60hp program. After that it didn't do it again for the next 200 miles there and the whole trip back.
I checked the code and it was a P0344 CPS A circuit intermittent Bank 1, but because of starting the truck so many times the light went odd before the trip home. I kept the tuner to stock tune after the light came on and the whole way home, don't know if this was just a coincident that it didn't happen anymore after that or ????.
Is the CPS sensor the problem? Wiring? Tuner?