V60/S60 D5 215 increased fuel consumption/DPF regen?
 

I noticed that my car all of sudden starts burning very high amount of fuel and the whole process seems to last around 30min. I used to believe this is something to do with DPF regen cycle but since my driving habits changed. Basically car is seldom driven in city and at least once a week goes on a long run. Usually 60miles round but recently 200miles round trips to the coast.

Even though car is quite regularly on a long run and in between is hardly used at all. Then once on the move while I am driving constantly 70-75mph all of a sudden fuel consumption gets a huge increase and average consumption sky rockets. It gets really annoying as this is not 10-15min cycle. Last time it happened I managed to get from Twickenham to Sevenoakes services where I stopped and resumed after short break.

Restarting engine seems to cancel the cycle. How often does this DPF regen is supposed to happen? I suspect a fault and I am gonna get it checked when car is getting serviced next week.

If the car is mostly city driven it's only natural that regen cycles will be more frequent. But I had a similar issue, too frequent regen cycles and that turned out to be the O2 sensor.

ECM-P2A0036 O2 Circuit Range / Performance (Bank 1, Sensor 1) - FM (Frequency Modulated) / PWM (Pulse Width Modulated) Failures - Signal frequency too low
ECM-P2A0085 O2 Circuit Range / Performance (Bank 1, Sensor 1) - Bus Signal / Message Failures - Signal above allowable range
ECM-P013022 O2 Circuit - General Signal Failures - Signal too high
ECM-P245800 Diesel Particulate Filter Regeneration Duration

Check engine light will not turn on.

I believe this is way too frequent and also lasts too long. I drive car long distance at least weekly, like I mentioned above. Missus was doing 10-11 miles round commuting trip with minimal traffic and steady 40mph run on cities dual carriageways.

I am having it serviced on Wednesday and will have it plugged to VIDA to see if anything bad comes up.

I did long cruise at 75mph on cruise control today and on the way back at around 110-120th miles of the trip bloody regen cycle kicked in. Momentary consumption doing 70mph around 8-8.5l/100km going flat vs 5-5.5l/100km with regen off. Range decreasing at alarming rate.

I will mention your suggestion to the service department. Thank you for your reply.

Stop don't drive it then, it can melt your particulate filter because of frequent high temperatures. Also have your turbo hoses checked because of these frequent high temperatures, the first one to go on these D5 engines is the resonator hose because it's screwed together from 2 parts, I'm suggesting a silicone hose.

I have no idea. Car does not seem to be experiencing power loss and speaking of temperature I have no idea. Oil temp seems to be normal the only odd thing I've noticed was when I sometimes switch it off like 5-10min into the regen cycle the radiator still works while engine is shut and certainly car feels a bit hotter but in terms of warning lights or any other bad symptoms there isn't any.

It's not the oil you should be worried about. There is 600-800°C in the exhaust system while the regen cycle is active, running constantly at these temps is only good for one thing - melting your particulate filter.