On city streets, I could usually get to 26 mpg and 34 on the highway. After having a bad battery replaced, and the charging system's software updated, the MPG is stuck between 19 and 20 mpg. I'm not sure if it's simply the meter calculating it, or if my car's gas mileage has gotten worse.

Thoughts?

 

A: It appears the trip computer needed to be reset. It was calculating the average MPG since the battery had been installed. So you use the button at the end of the turn signal switch to cycle to MPG, and hold down until it reads "0".