Had my Zed for almost a year. The MPG displayed is stuck on 32.8 despite varying how hard I drive the car. The was not an issue in the first few months of ownership.
The estimated miles remaining is functioning as expected.
Errr.... I'm absolutely sure you know this but just in case; try pressing & holding in the button thing at the end of the stalk for a few seconds, that'll reset it.
BTW, if I leave mine for a while it will always a avg at 32mpg too.
What a muppet I can't believe I forgot! I was certain I used to be able to reset the mpg! I've been resetting the miles driven past few months thinking that the mpg would reset in line. Going for a drive in a bit so ill see if holding the button on the stalk works again.