I have an 03 Sprinter which was a demo that I purchased in Sept 05 with 650 miles on it. I got around 22 MPG around town, on the highway empty or pulling a trailer (about 2500 #). At around 14K miles, the mileage dropped to 16 MPG same trips, same trailer and has stayed there since. I have changed the air filter and fuel filter. It has been to two different dealers for diagnostics and the answer is the same, "there is nothing wrong with it". The check engine light has never come on, so no codes come up. I am the only driver and I have been going very easy on it lately to eliminate my right foot as a problem. There is no difference. Obviously, something is not right. Does anyone have any ideas or has had the same problem