Or at least found out where it stopped! Left my mate's garage following a good service, and as it's a gentle incline down off Dartmoor, I basically engine braked almost all the way.... Seem's the average mpg doesn't go beyond this:

Impressive

It shows 200mpg on all PD diesels when in gear and no throttle if the car is moving as you describe.

It shows 200mpg on all PD diesels when in gear and no throttle if the car is moving as you describe.

.. and on the instantaneous mpg readout it reads - - -

It only starts to head toward 200.0 when on average mpg for the journey. I have just never maxxed it out before. Instant mpg was reading "-----" for most of the short journey from the garage.

By the time I got home though it was reading a more realistic 61mpg (biased still from overall drop in journey from 300m to sea level)

I can get 49.1 in the Fiat without even moving the car

My 04 TDI goes to 200 then back to ---. Sometimes I try and get it to stay on the 200 (downhill -problem is speed limit) just as a challenge. SWMBO's SDI goes all the way (The SDI does) and 300+ is easy. Oh gee am I reduced to this as my way of getting pleasure from motor vehicles?.........Argggghhh

I can get 49.1 in the Fiat without even moving the car

That's impossible in the fabia as I believe the instant mpg reads "------" on standstill tickover, but this actually means zero, as opposed to "infinite"