I've done just 60k km in the five years of ownership and for the first time the E53 X5's fuel consumption went to 12.7l/100km after having avereaged 12.2. The only problem I've experienced lately that I think might relate to this is the auxilary heater located under the hood has been coming on every time the car is unlocked.
I spoke with a BMW master tech and according to him, the functions of the auxilary heater is not used in Australia - only required in very cold climates. Replacing this unit will cost US$2600, and if it is not required to function is it worth replacing?
Anyone who can enlighten me whether there would be other reasons for the fuel consumption to go up?
Thanking in advance anticipating feedback