Mine is WAY off. It will read 33.6 MPG constantly... and then when I calculate the tank it is 35-36 MPG every time. It seems to read 2-3 miles low, but I'd rather have it read low than high. It's always a fun surprise to get the real MPG when you calculate a tank.

What I do find interesting is how the summer weather dropped the MPG meter. It used to read 34.9 or so all the time... and then summer hit and it went to the 33s and stayed there.