Hiya guys this is a strange one. Driving to work this morning down the motorway and my car's exhaust and engine sounds changed and my fuel economy seemed to improve.

I believe that the DPF system 'recharges/regenerates' from time to time and this can cause the exhaust note to change (sound deeper and throatier).

My fuel economy also improved by around 4 mpg too.

My commute is virtually all motorway (90-mile round trip) and i don't thrash the car.

Anybody any ideas? :confused:

....uhmm, when DPF regenerates mpg actually decreases, so it seems a bit strange to me...

Has your exhaust fallen off??

Time for the cage mod?

D

Yep might have to look at the cage mod.

In response to Ali_Wright, I did wonder if

my exhaust was screwed the other day! The same thing has happened on a few occasions.

I noticed increases as well as decreases in fuel economy during regeneration of the DPF.

The exhaust note you described seems exactly what mine does when regenerating. Can be very tiring, it is a much deeper note and it resonates more. Had it once in the city, thought it was the big Scania next too me...... (but this severe only happened once, rest of the regeneration processes I noticed, where on the autobahn).