Has anyone else experienced a sudden drop in their readings for AVG MPG? That happened to me the other day, as soon as I turned on my Commander the reading dropped really quick, I was at an AVG 17.0 MPG and it went down to about 12 MPG, it was odd. It kept dropping as I was driving. It has now come back up to 17.2 but it took about a week to return to where it was. Is this something that I should be concerned about? I'm thinking maybe a faulty sensor? Any ideas?