Filled tank and gauge showed full then some 70 miles on when out on moor road miles from anywhere i noticed gauge just over 1/4 and display 89 miles left to run. Checked in case of leak but all OK. Stopped at garage to fill and only needed 12.5 litres to fill. gauge then read just below 1/2 with 128 miles left in tank. Drove 145 miles home and it still reads exactly the same 128 miles left in tank.
Hope they fix it quick as I have 1000mile round trip next weekend. All FL2's (3) Gone
2011 Mercedes C180 CGI Gone
FL2 GS Auto SD with heated leather, factory tints, alloy spare and a few other bits.

I had a similar problem with my ex 57 MY. Tank half full but gauge and range zoomed up and down every few miles to zero and back during trip to Scotland few weeks after buying car. Also had 'reduced engine performance' warning during same journey. Cleared on refilling, into dealer on return and did not happen again. Presumed sensor problem. Sorry to see it is still happening on new cars! Upgraded to an ex demo, 7 mth old, Rimini Red/Ebony Napoli Auto HSE on 28th Jan 2011, added roof rails, mudflaps and side strips.
Gone - A great 57 Plate, Auto SE, Bought Feb 2009, Roof Rails and Mudflaps added on purchase. Blue colour, anything but drug dealer black.....

Off topic, but I saw a Sky prog tonight on Sarah Pallins Alaska. She was filling up a Camper Van thing. 240 quid for 86 gallons. Roughly 60p a lire. The beast did 7mpg!

Not exactly on topic, but we did a 700km trip up into the Victorian High Country last weekend, about 400kms on steep, winding paved roads, 100kms on fairly arduous off road 4 wheel drive tracks, including wading through a couple of creeks, and the remainder on normal roads. The onboard computer showed 10.8 litres per 100kms (mine is the 3.2 petrol version), the Garmin EcoRoute accessory, which runs off the diagnostic socket and GPS via the 1490t, showed 10.9 litres per 100km, and filling the tank against the last fill up gave 10.7 litres per 100km. So, the three different sources agreed to within 2%, which is not too bad.......I think!

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