Technical Anyone had luck deleting DPF and bypassing EGR? Fault Codes P0401, P0402, P0238 - 2016 Fiat Ducato 2.3L Twin EGR

[MSjoberg]

The way of tweaked LPEGR is a dead end. A lot of measured values results of the LPEGR - if they dont match the expectations, you run into other issues. I could think of dozends.

Your statement is very interesting. Maybe you can elaborate a little bit on what those dozens of issues could be (technically)? From my laymans perspective it seems that inactivating the LPEGR, if done right, will simply "downgrade" the engine from a Euro 6 to Euro 5 which of course is an issue from a non-technical perspective, but that is another question.


This entry (#956) indicates that it might be doable after all (I hope we will see more reports on the outcome in the future):

Ducato P0401 P0402 P0236 P0238 and limp mode its 2017 Euro 6, EGR changed, What do I check next | FIAT Ducato

To prevent any confusion , this is my current template 4 prefered for general testing. It is designed to do specific tests and point to other templates if other specific data is required. It also works with my semi automatic spreadsheet to produce the graphs. This uses live real time data and...

www.fiatforum.com

 

[theoneandonly]

heres a question, has any one done a DPF delete.
I understand that you may not want to broadcast this info , it may be legal or no issue in your country.
what i would like to do is charecterise with MES so we know what a Deleted DPF would look like. (got ideas but show me the data)
PM me in confidence. I all ready have data for HPEGR and LPEGR delete and a LPEGR delete on its own, but not a sieve removal and cracked DPF.

 

[priorphilip]

Your statement is very interesting. Maybe you can elaborate a little bit on what those dozens of issues could be (technically)? From my laymans perspective it seems that inactivating the LPEGR, if done right, will simply "downgrade" the engine from a Euro 6 to Euro 5 which of course is an issue from a non-technical perspective, but that is another question.


This entry (#956) indicates that it might be doable after all (I hope we will see more reports on the outcome in the future):

Ducato P0401 P0402 P0236 P0238 and limp mode its 2017 Euro 6, EGR changed, What do I check next | FIAT Ducato

To prevent any confusion , this is my current template 4 prefered for general testing. It is designed to do specific tests and point to other templates if other specific data is required. It also works with my semi automatic spreadsheet to produce the graphs. This uses live real time data and...

www.fiatforum.com

A friend of mine is doing Control Unit programming for Bosch on behalf of Porsche, on site (right here nearby). We had a brief conversation a few weeks back. We all dont know in detail what FIAT is doing but emission related calculation in general is self regulating. That means for example, if you eliminate LPEGR valve, you never get the amout of oxygen thats expected and injections are calculated incorrectly.
Incorrect injection values (post/pre/main timings) are key for optimal temperatures, NOx, particles, etc. Any single combination of incorrect values result in multiple following problems. Combustion with too high/too low temperatures, excessive fuel consuption, soated intakes and DPF. Probably others we never thought of.
FIAT for sure is not doing a great job in this area - but making it worse is not a way I would go.
Anyway, I will follow this thread and see where it is going.

 

[MSjoberg]

Yes, removal of LPEGR flow would increase the oxygen level in the intake which probably leads to higher combustion temperatures and more NOx. Question is how the control unit handles this. It still has exhaust temperature and oxygen data from the existing sensors and will react one way or another when these have changed.

 

[aschoots]

Jm2ct:
The way of tweaked LPEGR is a dead end. A lot of measured values results of the LPEGR - if they dont match the expectations, you run into other issues. I could think of dozends.
You've been peddling this nonsense for months now, without making any progress. Not sure why riding a dead horse is supposed to be a good idea.
Dont get me wrong, but thats not helping at all - for noone.

The only persistent and proven solution is to eliminate the obvious weakness in this LPEGR concept. The sieve is too dense and needs removal/modification for longer lasting.

I have to agree with you @priorphilip with respect to modifying the LP-EGR cam. With all parameters measured it will guaranteed the ECU will detect e.g. that O2 level is not changing when LP-EGR is opened and fresh air is closed, or that temperature does not reduce.

But I am also convinced the seive at the LP-EGR has a fine mesh for a good reason, you don't want particles travelling into the turbo or combustion chamber.

That is why I chose the following route; Unplug the LP-EGR connector so it won't move. To prevent errors and emergency running an ECU update cancels 24 errors. I am told the following list is blocked: 0409, 0402, 0401, 0101, C405, 0489, 0488, 0486, 061D, 2111, 2112, 060E, 0638, 0639, 061F, 044A, 045B, 045A, 045E, 041A, 046E, 041A (again), 213B, 213A.

I know I will need to track 'health' of the engine (more) myself now these errors are cancelled. I am told 22 of these 24 are directly related to LP- and HP-EGR operation which should not give problems, the other two are for communication with cruise control and the MAF sensor.
I want to check / this, and prepare a periodic manual check of engine health to ensure this error cancel does not hide anything serious from being detected.

Charts made of my first trip with this mod were made by @theoneandonly - see here: https://www.fiatforum.com/threads/d...nged-what-do-i-check-next.491167/post-4748552
It does not look like temperatures (at cat / DPF) are need for worrying.
In a diesel power is regulated through fuel amount, O2 levels between 0 and 21% (depending on engine load) indicate this.
O2 level drops to zero for a small moment, but that would have been worse if LPEGR was open / fresh air throttled at that moment.

 

[theoneandonly]

I have to agree with you @priorphilip with respect to modifying the LP-EGR cam. With all parameters measured it will guaranteed the ECU will detect e.g. that O2 level is not changing when LP-EGR is opened and fresh air is closed, or that temperature does not reduce.

But I am also convinced the seive at the LP-EGR has a fine mesh for a good reason, you don't want particles travelling into the turbo or combustion chamber.

That is why I chose the following route; Unplug the LP-EGR connector so it won't move. To prevent errors and emergency running an ECU update cancels 24 errors. I am told the following list is blocked: 0409, 0402, 0401, 0101, C405, 0489, 0488, 0486, 061D, 2111, 2112, 060E, 0638, 0639, 061F, 044A, 045B, 045A, 045E, 041A, 046E, 041A (again), 213B, 213A.

I know I will need to track 'health' of the engine (more) myself now these errors are cancelled. I am told 22 of these 24 are directly related to LP- and HP-EGR operation which should not give problems, the other two are for communication with cruise control and the MAF sensor.
I want to check / this, and prepare a periodic manual check of engine health to ensure this error cancel does not hide anything serious from being detected.

Charts made of my first trip with this mod were made by @theoneandonly - see here: https://www.fiatforum.com/threads/d...nged-what-do-i-check-next.491167/post-4748552
It does not look like temperatures (at cat / DPF) are need for worrying.
In a diesel power is regulated through fuel amount, O2 levels between 0 and 21% (depending on engine load) indicate this.
O2 level drops to zero for a small moment, but that would have been worse if LPEGR was open / fresh air throttled at that moment.

An alternate reason proposed for seive was as a spark arrester (whether it needs to as fine for this purpose i dont know, beyond my expertise).
If you want any data looked at, then post it or pm me initialy.

 

[priorphilip]

spark arrester

This indeed sounds like a plausible reason - but I would expect it even more at the HPEGR path.

 

[aschoots]

The seive functioning as a spark arrestor sounds a bit silly to me. We're talking ICE with direct injection. A combustible / explosive mixture exists only inside the cylinder / combustion chamber. There is no need to prevent sparks.

 

[priorphilip]

The seive functioning as a spark arrestor sounds a bit silly to me. We're talking ICE with direct injection. A combustible / explosive mixture exists only inside the cylinder / combustion chamber. There is no need to prevent sparks.

During DPF regeneration, post injections are triggered when outlet valves are open. Injected fuel is then burned when it hits the ceramics filter. This may cause some glowin ash particles to stream into LPEGR path. I bleieve thats what he ment. I understand that but I doubt its harming somewhere downstream.

 

[Fredastaire]

Just thinking outside the box.
.
Why is the filter mesh on the outgoing side of the cooler? Does the black dust/ soot arise from cooling the exhaust?
.
If it's there already pre cooler, as its sucked from the intersection between dfp/cat and the silencer, could we buy some 'same size' stainless mesh and incorporate it in a housing to be bolted in to the flex pipe (where you can reach it).
.
Then yearly, go under the van and undo this housing and flush it clean before refitting.
.
Much that this is wild thinking from the armchair with a cuppa in hand; does it have any relevance?

 

[aschoots]

Nah, thought about that as well, but that is upstream the LP-EGR cooler. There is a risk that parts of a 'condensed' soot layer from the cooler are released, and also parts of the (thin) metal (stainless?) fins on the exhaust gas side of the cooler could break and find their way into the turbo.

 

[Fredastaire]

I wasn't thinking of altering the existing cooler. Just a new extra filter by the silencer infeed.
.
It is the question of whether the 'soot' exists at the exhaust temp or does it only appear as a condensate form.

 

[Steve928]

I think that the 'spark arrester' was my suggestion and though I don't think it was silly (as pointed out above plenty of uncombusted hydrocarbons do exist in the exhaust downstream of the cylinders) I agree that it's not the purpose of the screen, which as we now know is a filter to protect LP EGR and eventually turbo from any form of particle downstream of the DPF.
The problem with the Fiat implementation is that the screen/filter is simply too small and anything but a perfect DPF will cause it to block. VAG have been using LP EGR filters since the EA189 engine (Euro5, perhaps before too) but their implementation must have about 25x the screen/filter surface area (pic below) so doesn't go tits-up at the first sign of soot.

 

[aschoots]

Pfff, difficult to answer in my view. The take-off is downstream the DPF, which should (!) be free from soot... But as we experience blocked cooler / seive, there is some soot present at that position. Soot is in fact a solid form of carbon, very fine particles.
In order to remove soot from the recycled exhaust gas stream a very fine filter would need to be installed.
To ensure pressure drop is not too high, the surface area of the filter would need to be large.
And given the exhaust gas temperature (350-400degC / over 600 during DPF cleaning') the filter material would need to withstand that.
I don't see an easy solution...

 

[priorphilip]

When I removed that sieve, there were no loose particles around.
No surprise to me, as the pipe to the EGR cooler is going upwards - while the vast majority of exhaust gas stream leaves the DPF straight into the pipe and silencers. Hard to believe that particles of noticable size is chosing the hard way upwards, driven by low airflow.
The more I think about it, the more it makes sense to remove the sieve completely.

 

[Fredastaire]

Taking an alternative view, I'm nearly two years in now with a replacement cooler, V32 and only run expensive diesel dosed with millers. Doing a data run with Multiecuscan my LP EGR temperature is running high and the LP EGR itself clearly blending variably as it should. I quite obviously don't know how long it will stay clear though.

 

[CheeseMonster]

When I removed that sieve, there were no loose particles around.
No surprise to me, as the pipe to the EGR cooler is going upwards - while the vast majority of exhaust gas stream leaves the DPF straight into the pipe and silencers. Hard to believe that particles of noticable size is chosing the hard way upwards, driven by low airflow.
The more I think about it, the more it makes sense to remove the sieve completely.

Could a 'deterioration / clogging / change due to age' IN the exhaust silencer cause the flow in particulate matter to change forcing more particles into the cooler as it ages?

 

[priorphilip]

Exhaust silencer probably not.
You may mean DPF? I would suspect broken ceramics, leaking Turbo, or something like that.
But moreover, it appears to be an incorrectly dimensioned part.

 

[CheeseMonster]

Exhaust silencer probably not.
You may mean DPF? I would suspect broken ceramics, leaking Turbo, or something like that.
But moreover, it appears to be an incorrectly dimensioned part.

No, I meant exhaust silencer. Just wondered if with age the back pressure increased through a reduction in flow.

 

[priorphilip]

No, I meant exhaust silencer. Just wondered if with age the back pressure increased through a reduction in flow.

Nope, there is nothing that can clog. Its just sheet metals that breaks sonic waves.