DPF service

[Caxap]

Didn't want to hijack other thread about good/bad of DPF removal. There are many slating threads about dpf/dmf/turbo etc. All considered, many issues people do understand how to fix but DPF is the right dark mystery. General conclusion on e-net forums:
1. Remove DPF and remap
2. Replace DPF and bend to be screwed at dealers

Few interesting suggestions were thrown by regulars on here about cleaning DPF. What actually is cleaning?
Pour magic juice into fuel system to burn off while regenerating?
Or remove DPF for special chemical cleaning?
How much do these procedures cost and where could it be done?

My DPF is fine, asking for niché advice so people would be better informed about their choices in future.

[Guest 2]

I haven't had a problem with mine in the 42k I've done in my A3 since Dec 2011.

Only problem was a Pressure Sensor which was changed under warranty.


Sent from my iPhone using Tapatalk

[-M-]

DPF clean or service is the next big con. The dpf is a filter so the soot turns to ash and is stored there - eventually all dpf's need replacing as it is a serviceable part just like a oil or fuel filter.
The system when running correctly carries out regens in the background and alerts you via warning lights when something isnt right.

A DPF service is literally you paying someone to drive your car and carry out a regen via a piece of diagnostic equipment.

The problem is everyone wants diesel economy but due to emissions not everyones driving is suitable for a diesel and they should therefore buy an economical petrol instead.

see DPF information (http://www.vwaudiforum.co.uk/forum/showthread.php?147028-DPF-information&p=818126#post818126) for more info

[Caxap]

Taking information from other threads people did state that replacing whole unit not always necessary and mentioned specific cleaning products (not sure about jet wash or coca cola treatment), it was mentioned that procedure is time consuming and messy and the reason dealerships don't do it simply because its easier to earn whack of cash by selling and fitting new unit instead.
Crasher mentioned something about Würth or such like, and I was interested to know and at times pass on information on alternative solutions to DPF service.
There are some preventative additives such as millers and forte but personally I can't say for sure if they're effective.
I use millers, it makes tdi engine work softer and slightly increase mpg, but DPF wise I don't know if there is any benefit. Although on bottle there is some marketing blurb about efficient burning etc to help.

[martin1810]

VAG DPF's are two things in one. A catalytic converter and a Diesel Particulate Filter. It is the DPF side of things that tends to cause problems. All DPF's filter fine carbon particles from the exhaust gas. These particles are believed to increase the risk of lung cancer so filtering them seems a good idea. The carbon collects as soot. At very high temperatures the soot can be burnt to produce Carbon dioxide gas so the filter becomes less clogged with soot. This is what regeneration is all about. BUT. The DPF also filters ASH from impurities in the fuel and engine oil. This ash build up cannot be burnt off and will eventually block the DPF. When that happens the DPF must be replaced. Washing it out may remove some of this ash. DPF manufacturers have agreed on a life 'ASH' collection time of roughly 150,000 miles so the DPF would last the lifetime for many cars and owners. So why do things go wrong?
The biggest problem with the DPF is how to work out when regeneration is needed. VAG use three basic concepts. Time and mileage to give some regular cleaning. Exhaust gas temperature calculations to help prevent overheating the DPF. Exhaust gas pressure sensing either side of the DPF. Anyone with a basic knowledge of physics will know that measuring temperature and pressure of hot, flowing, pressurised gases is a nightmare. The engine ECU does it's best and IF all the sensors work perfectly, the DPF will regenerate correctly and last a long time. Faulty sensors are the biggest problem because it is hard for the ecu to detect a sensor that is 'telling lies'.
I doubt chemicals to clean a DPF via the fuel are effective. Many chemicals would be destroyed during combustion in the engine and some could even 'poison' the catalyst part of the DPF so you wouldn't want them present. When it comes to dealers repairing/cleaning DPF's it is all down to cost vs time. With labour at over £100 and hour, which is cheapest, fitting a new part which will work or cleaning the old part and hoping? Most dealers don't bother to ask the customer because for them the answer is obvious. Fit a new part.