[gorsteve]

Hi Guys

I had a DPF issue where it blocked and wouldn't regen partly down to failed thermostats meaning that I wasn't hitting*the required temps. Got that sorted and now the car regens but it seems to do it a lot now, on a motorway journey every 150-200 miles the car is*doing a regen also the car got to 90k and only had 1.5 grams of ash and*over the course of 15k it has jumped to an ash amount of 3.95 grams. Is there something going on here causing excessive soot build up?

I have attached a capture of soot, regen and ash over about 250 miles. I would appreciate any thoughts, I have wondered about*mixture? Is the car producing too much soot, maybe*MAF or injectors?? Any ideas?

[Torqu3]

Are you driving it until regen completion? If you don't let the regen process complete, it may lead to what you're seeing.

[2011335d]

stupid question but how do you determine when a regen happens? also how do you find out the ash?

[JTC1]

Your ash mass seems really low even going to 3.95g for your mileage. Has your DPF been replaced or cleaned? My ash is running around 22-23g at 70,000 miles.....but we are comparing euro spec D to an US D, so I don't know how much that matters.

[JTC1]

Originally Posted by 2011335d

stupid question but how do you determine when a regen happens? also how do you find out the ash?

Only way I notice it is reduced power and fuel economy. Main way is by using OBD such as Carly to monitor. Easiest way to notice it while running an OBD is by the jump in exhaust gas temp (550-600 deg).

[Persian Whisperjet]

It's been (ahem) a while since a regen for me but if memory serves the regens came every 150-250 miles in normal use, or longer on road trips.

[Mark M]

Mine use to regen about once per tank of fuel.

[mefferso]

I average 400 miles between regens when driving 70% interstate

[gorsteve]

Hi guys thanks for the input. In answer to a few questions I measured the soot, ash and regeneration using Carly for BMW. The graph shown is from a 300 mile journey without stops so the car fully regenerated and then the dpf completely filled again and regen again. The bit that concerns me is that the car hit 95k on 1.5 grams of ash and then in the last 15k it has went to 4.5 grams now, makes me wonder if there is something operating outside of it's spec?*Maybe injector or MAF, something that*could mean that I am getting a lot of unburnt fuel. Just changed the oil with a flush to make sure that it is not oil contamination,*when researching where the ash comes from one thought was that it could be from impurities in the oil.