Oil level rising VW Sharan 2015 2.0 TDI 103KW

[davey_boy]

Cheers Crasher. When looking into the cat with the scope, is it absolutely obvious when the unit is beyond cleaning/regeneration? There's no rattling that I'm aware of so I'm wondering if I've maybe caught it in time, prior to collapse?

[Crasher]

I meant to save a picture last time but yes it is pretty obvious when blocked as you can see open channels and those blocked with grey crystals, usually in the lower section and sides.

[davey_boy]

2023-05-06-134524128.jpg2023-05-06-134533465.jpgphotos of the SCR filter

[davey_boy]

I put the scope up yesterday, adblue injector and its orrifice were clean as a whistle which i was surprised about, but the filter looks pretty clogged, is this what you saw on your unit, Crasher? I noticed that theres a fan like baffle welded into the SCR between the injector orrifice and the monolithic filter , i'm assuming thats why the cleaning guys say the unit cant be cleaned (with high pressure)?? I'm thinking i'll take the unit off and soak it with acidic cleaner, or worst case, cut the weld open and blast it directly with high pressure. Ive ordered a new Bosch Adblue injector too. Crasher, have you heard of anyone having any luck with an off-vehicle clean?

[davey_boy]

baffle.jpgphoto of the baffle welded in between the injector and the monolith

[Crasher]

That is designed to impart a swirl in the gases, that one is cleaner than the one we did a few weeks ago, you couldn’t see the lower 1/4 monolith.

[mickeybo]

The very very most likely place of oil mixing with water has to be the cyl head its self

[davey_boy]

I took the pipe off the car at the weekend and soaked it in 10% Hydrochloric acid for ~2hrs. Looking in with the endoscope wasn't giving the clearest picture so i decided to open up the pipe. Acid seems to have done the trick. Hopefully the active elements are still in place on the monolith. I will report back on performance once i refit. Getting the pipe off was a pig. The 3 retaining nuts were rusted to almost nothing, used the heat -up and rapid cooling method, then a nut removal tool. 2 came off ok, the 3rd snapped the captive bolt on the DOC downpipe, had a lovely time drilling that out. What an absolute crap design.20230514_113753.jpg 2023-05-14-111608739.jpg

[davey_boy]

someone kindly messaged me the link below on urea crystal removal

https://patents.google.com/patent/CN103111445A/en

[davey_boy]

Background on the 2.0L diesel engines at the core of the Volkswagen emissions testing debacle - Green Car Congress

An interesting article detailing the many components and multiple regeneration modes used for the different catalysts/filters in the exhaust system. If your driving use-case does not involve frequent long journeys, these modern diesel cars are not fit for purpose