Q: I purchased a new 55 plate X-Trail 2.2 dCi SVE in September and have barely been able to get more than 400 miles from a full tank of diesel. I work this out to equate to 28-29 mpg. Most of my journeys are under ten miles and at slow speeds. Is this fuel consumption acceptable? Matthew Haynes
A: Our figures suggest that you should expect 31.4mpg on what is called an ‘urban cycle' (designed to simulate slower town driving, such as you describe). We would imagine that your new engine is falling short of this figure as it is still bedding in. It is unlikely that a discrepancy of 3mpg would be deemed unacceptable by your dealer.
It is also worth considering that an engine's fuel consumption is markedly increased when the engine is cold. So it is possible that, given that the car is used for short journeys at low speeds, a figure of around 29mpg is fairly realistic.
To eliminate the possibility of other factors having a detrimental effect on your car's fuel consumption, we would advise you perform some preliminary checks if you have not already done so.
Make sure your tyre pressures are correct in relation to the load you carry, as extra weight can often require far higher inflation pressures. Incorrectly inflated tyres do have an effect on fuel consumption.
When starting the engine, do not depress the accelerator, and drive particularly gently until the temperature gauge begins to approach the normal sector.
If you are still unconvinced about the frugality of your engine, ask your dealer to perform a full engine diagnostics check, as this might identify a problem. This may incur a charge, depending on the conditions and expiration of your warranty.