Sudden drop in fuel economy- BiTdi

[Mo-S3]

My bitdi would happily return 44mpg on an easy run on the motorway and mid to high 20's local and being remapped it was fine.
Over the past 2 weeks its dropped massively to around mid to high 'teens and last night i struggled to get past 34mog whilst doing around 60mph !
This is really bad and wondering what could be the main issue for such a high drop in mpg.
Any idea's appreciated

 

[Buxton2901]

Is it possibly stuck in DPF regen mode? that would effect your MPG.

Or maybe a dodgy MAF sensor would cause in increase in fuel usage.

Let us know if you find a solution.

 

[fingermouse]

Brakes binding ???

 

[gary3306]

You didn't have any new tyres fitted did you? Also check the engine hasn't been overfilled with oil, believe it or not that can cause mpg issues.

 

[Mo-S3]

Well... DPF regen was last done 12.45km ago and no failed attempts in the log.
Rear pads need doing but no light on yet and not feeling any excess drag /noise
Oil is spot on and was changed around 3k miles ago.
Tyres are new but were changed last year.
Not had a chance to log any maf readings
Thanks for the tips so far