T6 Euro 6 204 DPF Delete, do you need a re map?

CheeT6

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Hi all, I may be opening a can of worms but worth an ask.

If I delete my DPF and re set the learned values (using VCDS) does one really require a ECU remap?

Its a 2017 Euro 6 204 T6.

My thinking is, if you reset the DPF values after a delete as if it was a new DPF install, surely the pressure figures would never change as there is nothing to clog up. Thus the ECU never needing to request a regen?

I'm fully aware of the MOT issues re a delete, I'm just getting my head around how and what's needed for the delete itself.

cheers in advance.
 
Don’t take it as gospel but by my understanding the re-generation process is triggered by the increased differential pressure across the DPF as soot accumulates.
If the differential pressure never reaches the set point the regeneration never happens.
It is more than an MOT failure to modify an emission system.
£1000 fine, no doubt MOT scrutiny will increase on these matters.
 
Don’t take it as gospel but by my understanding the re-generation process is triggered by the increased differential pressure across the DPF as soot accumulates.
If the differential pressure never reaches the set point the regeneration never happens.
It is more than an MOT failure to modify an emission system.
£1000 fine, no doubt MOT scrutiny will increase on these matters.
Hi DXX, yep im fully aware of MOT issues. TBH i can remove on of these in under 10 mins now, I've become quite a dab hand at it :cool:

So what you think is what I thought also, if there is no difference in the set pressure values then in theory no regen is triggered.

So if we are right, you do not need a ECU remap after a DPF delete?
 
Hi DXX, yep im fully aware of MOT issues. TBH i can remove on of these in under 10 mins now, I've become quite a dab hand at it :cool:

So what you think is what I thought also, if there is no difference in the set pressure values then in theory no regen is triggered.

So if we are right, you do not need a ECU remap after a DPF delete?
One way to find out I guess but it would involve removing or holing the DPF.
If you put a small bypass on the DPF it would still block without a regen’.
Major expense replacing the DPF when MOT procedure eventually catches up with you.
Plus; Chronic obstructive pulmonary disease (COPD)
 
surely the pressure figures would never change as there is nothing to clog up.



A quote from book by Bosch (editor Konrad Reif, 2014): "Diesel Engine Management - Systems and Components" suggests that there are some challenges ahead.
"The differential-pressure sensor helps to monitor whether the filter is possibly blocked, broken, or removed. The DPFsystem sensors are also monitored. Besides standard monitoring, the plausibility of values of the downstream differential-pressure sensor is also monitored. In dynamic operation, the supply line between the exhaust-gas system and the pressure sensor is monitored by a signal-curve evaluation circuit."

Perhaps could actually verify what happens - just by detaching the tubes from the differential pressure sensor.... I would place a bet on P2453 with flashing coil light on dash :whistle:


Moreover there definitely are even more hurdles along the exhaust after the DPF e.g. (1) a particulate sensor which obviously monitors the health of the DPF, and (2) the NOx sensor keeping track of NOx emissions. I'm fairly certain that both of them would also manifest their dissatisfaction.
t6_exhaust-jpg.26132


 
Not surprising that it’s been designed to be tamperproof.
There’s probably a market for a combined signal simulator to supply all the relative sensors.
 
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Perhaps could actually verify what happens - just by detaching the tubes from the differential pressure sensor.... I would place a bet on P2453 with flashing coil light on dash :whistle:
Good point, but worth a few experiments i think. I'm guessing there may a min required pressure or alike to stop things like this. but worth a play. could be a few weeks before i get a chance. life has well and truly overtaken any time or fun i get these days :)
 
Is it worth giving Darkside developments a call ?


 
CheeT6
I used to have a Audi A4 2.0 TDI which blocked its DPF. Solution was cut end off of DPF drill out breeze block weld back together. Get ECU re-programed which put all of the lights out. Car was miles better to drive and still passed its MOT. Car was a good bit smokier when you booted it. On the legal side you are breaking emission rules and robbing the tax man.
Baz
 
I appreciate all the replies but my original question really still applies. Does one really need a remap after a dpf removal? What does the remap do?
 
Hmm, VCDS suggests that the engine could be configured to run without DPF. However, not confirmed if EU6 engine would accept the change.
1633848734800.png
It's quite possible that the suggested bit is just a remnant of EU6 engine's predecessors - which (possibly) were sold outside EU without the same emission purifiers. Engines CAAA, CAAB, CAAC, CFCA on Transporters were certified from EU5 (on T6), down to EU4 and EU3 (= both without DPF). More here (p. 4-6)
Sorry, still no definite answer :thumbsdown:
 
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