Hi .. I have a few days ago bought a 307 convertible, 04 plate, 68,000 mileage, full service history. I am finding that if I set the trip counter to 0.00 and put petrol in the tank that the amount if miles I am actually driving is totally different to what the dashboard display says I am using. Ie I put in 10.00 and the display says I have 90 miles of petrol but I'm actually getting about 40. Do I have a problem?