I've had my 2013 XK coupe for less than a month, putting on about 550 miles of mixed freeway & street driving. Both the trip monitor and my Android mileage app indicate about 12.5 - 13.5 mpg. This is well below what I see reported here, and I'm wondering if this might be due to the recently discovered P2406/P0442 DTCs. The tech says these codes and other tests indicate a failed Evaporation Control pump. Could this cause low mpg?

BTW, I'm not a lead foot.

 

Yes they will