Ok I pumped gas,always turn the car off while doing it and tighten the cap until I hear 2 or 3 clicks.....my check engine light came on and got it read and it says...p0456......evap emission leak(very small leak).Thats exactly what the obII machine read...They suggested trying a new gas cap and erased the code but after a while it came back...They told me its not a serious issue and that I would have to bring it to a shop to get smoked.Is this true?Is this a serious issue?One thing I noticed is that my MPG is slightly off and the distance till empty sometimes goes from 307 dte to like 300 within like 2 miles and when I turn the car off and on again it would read normal.Is all this linked to leak?Thanks

 

I'm not sure what year your car is but for what its worth TSB NTB 10-057a covers this code you are getting. It's for all VIN numbers for 2009 Max's. The TSB is to change out the Evap Vent Control valve if is stuck open or leaking if it is closed.

 

I have a 2010,I'm bringing it Monday to get it checked our.Thanks

 

And for what it may be worth, the 'distance to empty' is simply a ball park figure. It gives us a good idea of where we stand on fuel, but is FAR from exact. The level of the gas in the tank can vary widely depending on the angle/tilt the car happens to be at any given moment. Also, the instantaneous MPG constantly changes, and that value is one of the factors used to calculate the distance to empty.

 

I had a lite come on after a fill up. Undid the gas cap, re set it , problem gone. what a crazy car. to much stuff going on at a time.