There are 5 XJ's in the family. They get different MPG though I have done as much as possible to keep them as much alike as possible(tires, cold intake, oil changes, tire pressure,plugs, etc) . The injectors was my latest attempt in keeping things the same. They are all autos. the 99 has a 2" lift. One of the 01's has the police package. Whatever it is, there is something that separates the MPG. The point is can I do anything about it?