DPF Trap 4.2TDi
 

OK Guys,

I've got a flashy coil light and MIL, and more importantly, no power at all really, limp mode is a bitch!

VCDS reports Particulate Trap Bank 2 has efficiency below threshold. Looking at some other posts, a swap is going to be scarily expensive, so I'm looking at 2 options here:

1 - DPF removal and re-map

2 - Clean them myself, but that probably means I need a ramp to get to them.

Anyone got any experience on number 2? Bloody typical that it happens on a Friday afternoon when I need to drive to Manchester on Monday morning.

Or... if I forced a regenerate cycle with VCDS, might that sort it out? It'll clear , but after a bit of gas, it comes back :(

Could try giving Brotek a call, remember the guy we met at Glasgow Audi? know he does removals and remaps all the time

http://www.brotek.co.uk/

The DPF removal, decode and remap I had the 4.2 Tdi Q7 was well worth it.

Worked out at about £650 and would have cost more than that to fix the DPF sensor.

Car is quicker, more responsive, a little bit more fuel efficient and has developed a lovely subtle V8 purrrr... +++

I was a bit dubious to be honest, but now I've had it done once any can that has a DPF failure I'd take the same route no questions +++

I almost wish my A8 had a problem then I could justify the 'fix'... ;)

As far as I am aware there is no way to physically clean them. Forced regeneration or long drive in low gear highish rpm might help depending on the sate of it.

A chap we knew locally has had the same issue on his Q7 and he tried the long drive high revs method and it has cleared his and not come back to date. Might be worth a try at that first Richard as the easiest fix, then a regenerate cycle next with VCDS then if no luck go down the remove, code out and remap route +++

Can't do the long drive/high rev thing as it won't let me above 2500 really as it's in limp mode. All the reports I'm reading seem to suggest that once it's at this point, unless you strip and clean them (not a guaranteed fix), then you could potentially burn the car down with a forced regen due to the increased temps as the regen on these engiines means you sit stationary for 40 minutes.

£850 all in for the stage 1 shark map and DPF removal from Brotek seems fairly reasonable and risk free (oh..and 50 free horses too)

I see no reason why the 4.2's DPFs shouldn't be cleaned like those on the 2.0.
Here is a german thread on the cleaning of the 2.0 with important tips as how to force start regen, then pressure clean them DIY.

http://www.a4-freunde.com/showwiki.p...spuelen&page=2

VERY IMPORTANT:
Before removing, start a forced regen via VCDS, then immediately stop and remove. There can't be any oily residues in the DPF, as this prevents pressure cleaning and will destroy it.
Every opening for difference-pressure-sensors, Lambda-sensor and Temp-Sensor have to be closed with screw or appropriate measures.
Clean with a rotary nozzle AGAINST the flow of exhaust gases.
Use pressurized air to dry. Then some hours on a radiator.
Use some non-stick medium for the screws when reattaching.

There is some info, as how to set the Ash-amount in VCDS, but I haven't found the according blocks in VCDS myself yet for the 4.2.


If needed, I can translate more tomorrow, as I am off for another Audi-meet.+++

I have a 3.0 TDi, and had the DPF hollowed out by a small VW specialist.
(it is a catalyst and DPF combo) with a small catalist before the larger DPF all in one unit.

They removed it and used a crow bar to smash out the internals in the back yard then refitted it. The man who did it was as black as your hat and so was the floor. He said he never wanted to do that again!
They got some mobile chipper in to remove the DPF software.

Unfortunately, as I wasn't quick enough taking it in, the back pressure blew the turbocharger centre gasket between the two halves, so had to get a new one of those fitted too.

Has better performance, not sure if it was remapped at the same time, but mpg is no different.

It's going into BroTek week of 23rd as that's the first date they have, so it's a fortnight in the Volvo for me as I don't want to drive it about and risk further damage. I could try the cleaning method, but looks like it'll be a barsteward in mine as there looks to be a long piece of exhaust pipe on the back of them.

So what about the planet maaaaaan? You shouldn't have bought a heavy particulate, global dimming, tactor fuelled car if you're just going to remove parts that help keep my kids lungs free from the nasty pollutants those oil burners chuck out :p

Once deleted tho would you (legally) have to get the car reclassed tax wise as it must be a heavier pollutant or is it not, as it's done on CO2 and the DPF removes the bits that kill my kids?