Kristian,

I've had a Scan Gauge in my HCH2 since December. It doesn't work well for me for exactly the problem you reported. If you ask me, the Scan Gauge guys have a bug. I've talked with their tech support (which is very prompt), but nothing they've recommened helps it reliably show 9999 MPG when I know it isn't using gas. The last suggestion they had was to change the data sampling rate to FAST which didn't help.

A couple of weeks ago, there was a discussion on this forum on the same topic if you want more info:

http://www.greenhybrid.com/discuss/f...er-both-18830/

Personally, I think there are more interesting products on the market. But for all I know, they'll have the same problem interpreting the OBD-II data correctly. I probably wouldn't buy a SGII again.

Have you seen the Kiwi? http://www.plxkiwi.com/index.html

-dan