Since I bought the car 2 months ago I have been doing the same trip to and from work every day. In the beginning I was seeing about 47-48mpg. Somedays when it was a bit more clear I would see 50mpg. However, over the last 2 weeks this figure has dropped to below 43mpg. This morning I was down to 42mpg! (note; all figures are trip averages!). Is there any reason this may be happening? I have been trying to think of external factors that may be affecting it, but can only think of the change in weather as I haven't changed anything with the car. A few days ago I did replace 2 front tyres and went from the Dunlop Sports to Goodyear Excellence. However, this problems is older than just a few days so I can't see that being a deciding factor. If anyone has any ideas I would be most grateful. Please note all mpg figures are for a UK Gallon, not a US Gallon! My car is a 2002 130TDI Sport. THANKS!