D24 tic fuel issue

[jpliddy]

hi all
i have the d24 tic in my 940 volvo it has always returned 30ish mpg since I've had the car 38 mpg on a good run 16 years now
just filled up and its calculated 26 mpg most of this milage has been short runs
on this tank
its the lowest I've had pretty sure I've got no fuel leaks and had new volvo
/ bosch injectors 2 years ago so would have noticed it by now as i do a calculation at every fill up also been using a shot of millers diesel clean
for the last 10 years or so
suppose i need to take it for a long steady run you would say
I've read somewhere you can adjust this engine a bit to make it more frugal
but never touched the pump / timing but did have it checked few years ago and was fine .
any comments most welcome

[Goteborg Vapenfabrik]

There's plenty of confusion with regard to measuring fuel economy. The metric system, US gallons and Imperial gallons. Since you own a 940, and are referring to miles, ill assume you are in the UK. 26/mpg Imperial would be a bit low. However winter mileage can be quite dismal. Are fully synthetic lubricants in the engine, transmission and differential? It could as simple as a low quality batch of diesel also.

[jpliddy]

hi goteborg
thanks for your prompt reply.
the engine oil i have used since i had the car is millers xfe 10 40 semi synthetic changed every 5000 miles and filter too
i am hopeing to change the diff oil early this year as its never been done.
i will use castrol synthrax 75/80 thats whats been recommended
just hopeing its all the short journeys I've had to make recently
my car is the auto but have changed the auto oil recently