Owned from new 58,000 Miles, mostly dealer serviced. Brim to Brim fuel consumption was normally better then 50mpg - onboard "this journey" consumption occasionally as high as 60 mpg but this tends to be up to 5mpg off the mark. Slightly lower overall during winter months.

Since last December now between 40-45 mpg driving very carefully. New cambelt late December but fuel consumption had dived before that so cant blame the installation.

Can see no logical reason for this, no ECU lights, or smoke, driving/journey style much the same, VRS mode has always been selected, performance seems unaffected. Has the forecourt diesel mix been f@cked about with by the bureaucrats?

Can anyone recommend an injection specialist/proper diagnostic technician as I don't wish to use a main dealer to resolve this - in DEVON please.

Thanks

2 hours ago, JTBS said:

Can anyone recommend an injection specialist/proper diagnostic technician as I don't wish to use a main dealer to resolve this - in DEVON please.

Any branch of Turner Tune or Bosch Diesel.

Post your updates when you get this checked out.. 

 

 

I too have a similar issue and have no external signs or errors showing any possible issue. 

My car has driven double your miles. 

My attention is on the intake part of the engine. Throttle body more specifically. It does get clogged with deposits from recirculating air from the turbo and pressure release from the engine, carrying oil deposits. 

Well documented issues for all diesels. 

My garage has to find some time to book me in to examine these aspects and do an injector clean depending on the amount of deposits found in the throttle body Intake area. 

Logically trying to eliminate issues rather than tackling everything at once. 

 

 

Throttle body clagged up should be the first thing to investigate.

Mine had a similar issue. Things to consider:

 

DPF cleaning ? If full 

Oil change service? On time ? Oil type etc 

Injector cleaning 

Carbon clean

Sticky callipers?

 

On 25/05/2023 at 22:57, seneca009 said:

Mine had a similar issue. Things to consider:

 

DPF cleaning ? If full 

Oil change service? On time ? Oil type etc 

Injector cleaning 

Carbon clean

Sticky callipers?

 

DPF is OK

Oil Change and filters up to date

Calipers Ok

Tasks to check are Throttle Body Carbon Cleaning

Injector Cleaning 

 

Will update soon as these are done and have some feedback on the economy. 

Urgent work is to replace the DMF and Clutch which was just ordered as out of stock for over 1 month

Many thanks for the replies, I didn't realise there were any answers.

Oil has been changed with a recognised fully synthetic C3 oil along with filter at the appropriate intervals.

The brakes are not dragging as discs are cool to touch after a run with little braking.

I have noticed the inbuilt DPF system cleaning doing its thing a bit more often than before, although I have taken the opportunity to run the car hard up the local steep hill, Telegraph Hill and Haldon Hill, both steep enough to get the oil temp up to 106/107 on occasions.

Induction system and DPF cleaning is the way forward I think.

Today - this morning, ambient air temp 5-10C the onboard "this journey" consumption struggled to get to 46mpg (approx 40 motorway miles plus 10 through 30/40/50s. Returning this afternoon onboard "this journey" consumption 56mpg - which sort of suggests an air temp sensor problem?