It is a well known issue in North America, more so after the Volkswagen fix. I am not sure how the DPFs are fairing on the newer EA288, but on the older CJAA engines, etc they are failing at a good rate. I have been through three since the Volkswagen emissions fix, in 60,000 miles of driving. It continues to happen and was a reason for the national shortage of DPFs last summer.
Funny thing is, almost every TDI I see in a parking lot now has black soot in the exhaust tips. You used to be able to run your finger in the exhaust and it would come out clean.
Yes the early dpf's did have more regen trouble, 2009 especially and the system must have been tweaked by 2011. Since then I'm not aware of any panic level issues. Don't get me wrong dpf's are getting full and being replaced. However this is due to other issues and the dpf 'replacement' being wholly unnecessary except in the case of cracked dpf's (ie soot in the tailpipe with dpf installed)
A few of the common case studies, customer:I got a dpf problem, fault light on. Garage: let's replace dpf. Customer comes online forums says I got dpf problem. He is asked what did you do. He says
I fixed xyz and left exhaust clamp loose. I kept driving the car so soot loading is now so high it won't allow regen, not even standing regen. Best Solution: now clean dpf and ensure exhaust clamp is sealing. Possible solution 1:replace dpf. solution2:delete system, remap ecu.
A second common case study: Customer:my dpf is blocked. Garage: you have fault codes for egr/throttle valve, and dpf. Lets replace the lot. Real solution: identify actual problem with
egr/throttle body and rectify as required, go on a drive and allow dpf to regen, cost: as little as 1 can carb cleaner. Labour might require some hours though
Case study 3, customer: I look after my car but keep having EGR and dpf issues. Upon a thorough investigation he says
I use a brilliant expensive oil at service. Upon further investigation it is found that brilliant expensive oil does not meet vw ash content specifications 'c' rating. Solution clean EGR, replace oil to correct specification, regen dpf.
I hope the above makes sense. The dpf's themselves do not have issues impeding regen. It is always something else (except in the case of cracked dpf's in North America.). The dealer ecu software has caused some trouble as well on some models but again that's an external issue to the dpf itself.
So as far as my research into the matter over the last few years has concluded, the dpf's are bulletproof in that they are not at fault themselves. I hope you can see where I coming from
