Fuel consumption is worse despite improvements.

Hi.

My D1 gave me 31 mpg just under a year ago and this was constant over a number of tanks.

Since owning I have had new tyres (standard), cam belt change, shocks and springs replaced, polybushes on rear (rest of them to do), recent new fuel filter and air filter, coolant change. All of this was pretty recent.

However, I am now only getting about 27-28 mpg despite all the above.

Am I missing something obvious that I should be doing to retain my previous and better MPG.

thanks.

Check brakes and are the new tyres less energy efficient?

Can cam belt timing be ever so slightly out? just a suggestion im not an expert on them

Hi,
Did you by any chance start experiencing the reduction in fuel efficiency after the cambelt change?
Had a similar issue after mine was done a couple of months ago and it turned out that the timing of the fuel injection pump was too retarded.
One telltale sign of injection timing being too retarded is the engine running a bit quiter than before the cambelt change and higher exhaust gas temperatures (without exhaust pyrometer or any temperature measuring device, you can tell by looking under the bonnet after a hard run; exhaust manifold looks almost white hot)

Hi. New tyres are no different to old and forgot to mention did also change discs and pads too.
Good point about the cam belt change, I wouldn't have know that. I recall the change may well have been about that time.

Possibly worth investigating.

Many thanks.

HarryPearce said:

Hi. New tyres are no different to old and forgot to mention did also change discs and pads too.
Good point about the cam belt change, I wouldn't have know that. I recall the change may well have been about that time.

Possibly worth investigating.

Many thanks.

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Check your tyre pressures Harry, make sure they are: 33psi front 36 psi rear.

Also make sure the brakes (albeit that they are new) are not dragging.

Hi, I'm not so sure about these tyre pressures, the handbook gives 26 front and 33 rear for 235 70 R16's, I run 28 and 34 and find that much more than this makes the car bounce a lot and wander at speed. The older 205 wide tyres used to run at higher pressures.