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Fuel consumption suddenly dropped?

Last year my Jaguar X-Type diesel's fuel consumption suddenly dropped from 52 to 44mpg.

I have put two lots of injector cleaner in the tank; changed the fuel & air filters; checked the MAF and DPF operations and the car still shows no faults on a diagnostic check.

Is there a common cause for this sudden change? My local garage say it is cheaper for me to continue to use it than it would be to diagnose and repair a problem!

I use the car for short local trips and also 250 mile motorway journeys.

Asked on 4 April 2013 by Daimler_SP250

Answered by Honest John
Various people offer stuff that is supposed to sort out the DPF. It might be that the DPF is not functioning properly and that the ECU is injecting excess fuel into the engine to try to clear it. Check the sump level. If that has risen, then this is is what is happening to the fuel.

Real MPG enables you to register the fuel economy you are actually getting against your make and model of car, its engine and type of transmission.

Every time you enter an average consumption figure against your car, the overall average automatically adjusts to reflect it.

Real MPG
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