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

[deejays]

@MSjoberg @theoneandonly @Fredastaire According to FCA Service News 10.17.09 of 14/04/2009:
"Injectors:
The incorrect FBC value (Fuel Borne Catalyst or injection time correction factor) is analysed by means of EXAMINER
checking that the FBC of the single injector is comprised between -2 and +2 mm3/injet with the engine idling and
warm.
The incorrect FBC value generates the following problems:
-high particulate production-regeneration cannot be run.
Solution:
This problems may be solved in principle as follows:
-check correspondence between IMA injector codes and injector codes written in ECU.-try to reset self-learnt injection
amount.-replace the injectors."

So, at least that confirms the test is carried out with engine warm and at idle. And it seems that if outside that tolerance, the DPF regen cycle is prevented from occurring - probably as a safety control to prevent over fuelling on Post Injection and burning the DPF (the DPF just gets blocked instead!). But, that does not explain what is occurring for those with injectors within those test values.

If you are wondering where I found this info, it is buried in the following document which you can find in the "Downloads" section:

 

[MSjoberg]

@Fredastaire @theoneandonly With reference to the clutch calibration - I guess it depends how the new SW update is applied. For example, it is possible that all calibration settings are kept (stored) and SW update applied and all calibration settings restored.

I guess the settings are kept and the new SW version will continue with the same settings as the previous version.
The purpose of the Clutch self-adjustment procedure is described in the Fiat training document as: ”…to quickly recalculate the ”Kiss point”, i.e. the position at which the clutch starts to transmit engine torque”.
I assume this implies that the historical Kiss Point data, which according to my knowledge is gradually updated at every engine start in order tho compensate for clutch wear, is deleted. So you get a faster adaption if something has happened with the clutch (e.g. a recent mechanical stepwise self-adjustment of the pressure plate (a feature in at least some models)).

 

[proppb]

Just seen this on facebook if anyone in the uk is interested.

 

[deejays]

@theoneandonly @Fredastaire As requested (via email) attached T4 for 2018 V32 in good order.

 

[theoneandonly]

@theoneandonly @Fredastaire As requested (via email) attached T4 for 2018 V32 in good order.

Comments in order of remembeering
DPF sensor working asit should , good values not indicative of a blocked dpf as is the regen graph about 70%
hpegr working not stuck
lpegr temperature in band of perfect working sample engines (about a 30 degree ripple) the valve opening values indicative of a good working engine, abolutely no issues obvious.
turbo pressure ok at topend generaly achieving close to demand
Injectors, good results achieving fiat limmit at high revs. similar to @Fredastaire
O2 sensors working ok as good engine
DPF temperatures ok.

So to wrap it up Id be happy if it were mine, far better injector values than mine. Cant see any problems on horizon.

 

[deejays]

@theoneandonly Excellent work! Are you still considering whether to update to V32 from your current V28? I know you have a personal interest in the data for your own vehicle health, but it is commendable that you publish the results along with comments as it will be invaluable for those who may be trying to understand their vehicle and also the workings of MES. Of course, anyone with a registered version of MES can simply download the file and import into their copy of MES to view in the graphs tab. Cheers, and keep up the good work - it is appreciated by many.

 

[theoneandonly]

@theoneandonly Excellent work! Are you still considering whether to update to V32 from your current V28? I know you have a personal interest in the data for your own vehicle health, but it is commendable that you publish the results along with comments as it will be invaluable for those who may be trying to understand their vehicle and also the workings of MES. Of course, anyone with a registered version of MES can simply download the file and import into their copy of MES to view in the graphs tab. Cheers, and keep up the good work - it is appreciated by many.

Thank you for your support.

last year i tried/concidered updating but the Fiat Pro network over here is very "variable" in ability and trustworthness. I tried my local dealer for an update and they refused said they would do it with a service or with a cambelt change that I needed for 1300 pounds i talked to a Fiat pro gararage in Portsmouth (reccomended by folk on a Motor home forum). It appears they are one of the few that actualy understand the comformatic and are prepared to sort them out. So a 240 mile trip (instead of 6) and they did the cambelt and auxhilaries (pump not leaking so not required, Fiat expect the original to last 300,000 miles.) I talked to technicion yes it went on the machine ( he asked me had i deliberately created errors because he found one hed never seen before amoungst other which he cleared old ones , not me Guv honest) later on I did think i may have created some with my "investigations". We talked about updating and his reaction was "bloody forums" . Since there was no campaign to update manuals beyond V28 or any of the required errors the machine would not update. I protested too much, my mate (an other forum ) had a service in august (22) yes thats a comfortmatic it has a campaign, you dont need it, i cant do it. Now I/we know that some manuals have been updated to V32 but that has been at customer cost and maybe required alternative methods that my guy wasnt prepared to do. Cost was 740 pounds. By the way the local dealer was part of a group that had its franchise removed by Fiat. So am i happy i have V28 Yes.
Mines a nov 2016 (manual) out of factory reg March 2018 and ECU updated march2019 within 3000 miles.
As yet no problems (excessive leak off on cylindar 3). The real problems were poor programming especialy regen which caused excessive temperature durring regen cracking the DPF leading to blocked LPegr cooler.
durring this period injectors were also knakered.(6 software versions from first to march 2019) So taking the view that V32 is a recovery version or mainly for Comfortmatics, Fiat had the oportunity more than once to tweek any cock up i may originaly had.
I have looked at data ive got Vans with Problems 17% manual 83% comfortmatics 130 70% 150 30% This are from small numbers I am going to go through these numbers to try to fill in gaps and improve statistical reliability. I didnt intend this type of breakdown initialy so some empty slots.
I have confidence i wont have LPEGR cooler problems, in the beggining i had a personal interest in the data for my own vans health but have this need to help people on the way to me understanding whats going on. Helping @Fredastaire on assessing health of his motor with minimum intervention helps us all. More data on actual regens not the average data in MES is needed (even that on a number of machines may help).

 

[ravy]

Hi Fredastaire

The meaning of these codes in a Ducato context (as far as I can tell) is as follows:

P0401 Exhaust gas recirculation flow insufficient

P0402 Exhaust gas recirculation flow excessive

P0236 Turbo boost sensor range/performance. (Measured pressure greater than commanded)

P0238 Turbo boost sensor input circuit out of specification (High boost reading when no boost demanded)

I suspect that the monitoring of EGR system performance is done partly indirecly, i.e. it includes readings of manifold pressure / boost derived from the Manifold Absolute Pressure (MAP) sensor. So a fault in the MAP or its wiring could result in an EGR system error being flagged even with no fault in the EGR components.

The P0236 and P0238 codes suggest a fault with boost pressure or its measurement, and the "limp home" mode is a precaution in case there really is excess boost pressure. Replacing the MAP sensor and checking its wiring and connector (as you plan) would be the logical next step. These sensors have a tiny hole between the manifold end and the internal semiconductor chip that measures the pressure, and this tiny hole is at risk of being blocked by oily deposits. Cleaning isn't impossible, but these parts are relatively cheap so replacement is probably the better option.

@BobSlo please send me a personal message with your email address. I'll send you screenprints of what I record now each longer journey. I strongly recommend you await to receive your MES and do some testing. from my personal efforts I dont see the need to replace the HP EGR, you can first look with MES and see it operating so you will know if its opening and closing. If you remove it then take off the servo motor you can operate the valve with your thumb to see if its sticking, then clean it with dilute Caustic Soda, takes minutes, I was flabbergasted at how quick it was to clean. Then you can look at the DPF readings and see how blocked up it is, there is a crazy figure of 100% which is sort of full yet MES says even greater % is still fine. My other european contact guy has been working on a clients Ducato to do a forced regen from 380% down to 40% at which point theyve handed it back to the customer, (No I havnt misstyped 380%). With MES you can see how many self regens its done since new, see how many KM it averages between regens to give you an idea of when the next regen is. I know that my DPF is self cleaning according to plan so I know I havnt a DPF problem. I still think that my cooler is probably blocked which is causing my 'soft code 0401' to be in memory, I'm hoping that somebody will come up with a method of getting at the cooler without removing all the subframe and steering rack. Maybe you can unbolt the engine and lift it up and forwards a bit and remove that DPF?
With MES you can do a drive and get your passenger to monitor airflows and pressures, for my Ducato I can see that the actual figures follow the requested figures so in normal driving I know that there is not much wrong, (I hope ).
Equally it would be good if somebody could do a remap and delete the LP EGR, I wouldnt delete the HP EGR though as I do have some responsibility for the environment. The Fiat twin egr system is just too complex.

 

[Fredastaire]

@ravy , you've added 2 previous quotes but not asked any questions.
.
How can we help you?

 

[kangexpress]

Hi everyone,

I'm back after some time away.

For those familiar with my story, you know that I've invested a significant amount of money, which eventually led to four new engines for my four Fiat Ducatos of this engine model.

Now, after 300,000 km on the new engines, we're back to square one—the same problems are starting again.

We already know that we can monitor the LP EGR Cooler temperature and the airflow values.

I've recently discovered an easy way to test whether the LP EGR Cooler is indeed the cause of the problem.

There’s a temperature sensor located between the LP EGR Cooler and the LP EGR.

If this temperature sensor is removed from the pipe, the necessary airflow can pass through the opening where the sensor was installed.

During my test drive before removing the temperature sensor, the LP EGR temperature values were between 40-50°C, and the actual airflow was consistently above the desired airflow.

After removing the temperature sensor, the result was clear: no more limp mode, and the low RPM performance has significantly improved. The live data values now show that the desired and actual air flow are the same.

So, it's confirmed—my LP EGR is clogged again.

I'll be installing a new one soon.

And if this one clogs up again, I’ve thought of a solution: replacing the temperature sensor with a pipe hose and installing a pipe that leads into the air filter housing. This way, there will be a bypass for the LP EGR Cooler, which than can remain clogged.

 

[theoneandonly]

@kangexpress , good to see you again, but not for the reason.
you may have seen this

Ducato twin EGR Engine with P0401 Code (2016 to 2019)

This does not refer to earlier single EGR systems or to later AdBlu SCR engines. Note this is a guide and not definative. It is up to you to make decissions. It is the result of my investigations of data from many contributors and discussion with...

www.fiatforum.com

I now find it quite easy to tell when a egrcooler is blocked but not how far down the route it is. The temperature and the opening charecreristic of the lpegr value give the clues. Simply put Rapid opening and closing its blocked, variation between 2 and 4 its under control.
But back to you. the sensor is not accessable from the engine bay and requires a lot of stripping down? is it feasible to put a T piece in the temperature sensor hole and run an extention pipe into the engine bay. this pipe is then normally blanked off but when blocked can be used to introduce a dpf cleaning fluid into the cooler and cleaning tea strainer and main cooler. If so this could be an anual / periodic cleaning technique.

 

[Fredastaire]

@theoneandonly , the LP EGR temperature sensor is the wrong side of the cooler to add cleaner.
To attempt cleaner it has to be fed in at the flexi pipe that connects from the silencer.
I noted that the LP EGR opens on engine start up from cold, (I've only looked once).
I'm wondering if it's possible to undo the ring clamp at the silencer; part the flexi away ; blank the silencer tapping, with a cold engine start it and with MES showing the EGR opening spray a DPF cleaner up the flexi.
.
Alas I'm conjecturing from the armchair.....

 

[kangexpress]

@kangexpress , good to see you again, but not for the reason.
you may have seen this

Ducato twin EGR Engine with P0401 Code (2016 to 2019)

This does not refer to earlier single EGR systems or to later AdBlu SCR engines. Note this is a guide and not definative. It is up to you to make decissions. It is the result of my investigations of data from many contributors and discussion with...

www.fiatforum.com

I now find it quite easy to tell when a egrcooler is blocked but not how far down the route it is. The temperature and the opening charecreristic of the lpegr value give the clues. Simply put Rapid opening and closing its blocked, variation between 2 and 4 its under control.
But back to you. the sensor is not accessable from the engine bay and requires a lot of stripping down? is it feasible to put a T piece in the temperature sensor hole and run an extention pipe into the engine bay. this pipe is then normally blanked off but when blocked can be used to introduce a dpf cleaning fluid into the cooler and cleaning tea strainer and main cooler. If so this could be an anual / periodic cleaning technique.

The sensor is accessible if you remove the battery and the battery tray.

It's just underneath.

14 mm spanner is needed to unscrew the sensor.

 

[chumleywarner]

Hello everyone - a newby to this 3 year string of information and what a journey it has been and I take my hat off to all those concerned for your patience, persistence and knowledge. I am also a relatively new owner of a dreaded Fiat Ducato 2.3 multijet twin egr motorhome - it is a 2017 plate with comformatic semi-auto gearbox. I absolutely love my MH and love the style and layout of the van so have no intentions of selling up and happy to work around the frustrating engine issues as so many of you on here have also done. My vehicle has just covered 27k miles and I have only owned it since October 23 and only now starting to have EML error codes. For ease I am attaching my MES scan confirmrng exact make and model.

I have so far had the following recurring ecu errors flag up (they have come up 2-3 times over the last 300 miles and always put the vehicle into limp mode.

P0238 [0x0238]
Turbocharger (TC) boost pressure sensor A/supercharger (SC) boost pressure sensor A - high input
turbo pressure - low pressure,
Status: Confirmed
----------------------------
P2002 [0x2002]
Particulate trap, bank 1 - efficiency below threshold
Resistance to air flow in high particulate filter, Plausibility
Status: Confirmed

I have so far not had the P0401 or P0402 errors but I think it might only be a matter of time.

From several days of bedtime reading through this mammoth string of comments dating back to 2021 this is what I have learned so far:
1) The most likely culprit of most of the subject related ecu errors lead back to the LP EGR clogging which is apparently very difficult to get access to clean or replace (circa 8 hours of man time).
2) There are issues with the vehicles Turbo Pressure Sensor which seem to fail around 30k miles and this probably ties in with my recent P0238 error. I believe these cost around £75-80 (Pierburg)
3) The MAP sensor is also prone to clogging or failure - some vehicles have been fitted with the wrong part number from new by Fiat but not sure whether this is a problem or not but a new correct part is around £52 (Bosch)
4) The injectors can be temperamental and their performance should be regularly monitored to reduce issues with sensors and DPF clogging
5) The ECU firmware is best to be updated to the latest v32 as this will help improve various engine management processes to reduce the chances of the error codes and clogging of the LP EGR/DPF
6) It is sensible to fuel the vehicle with Super Diesel rather than standard to support regen of the DPF to stop it clogging and keep the injectors in good working order


Please advise me if any of the above are incorrect asumptions or anyhting else important that I have missed as I am in no way experinced in engines or engine management!

So right now I am just trying to get a full working version of the MES software running so i can record some tests to share as I think @theoneandonly has the expereince to advise what issues I may have from these graphs and what my best cause of action will be to resolve my current ecu errors - I am assuming there would be a cost for this so please advise. I am not sure how to communicate directly with specific members of this group so again please advise of this is possible incl @Fredastaire? I have so far tried connecting my iPhone via MES but I don't think it has the the ability to record anaytics and transfer these recordings to an email so I can forward them for review. I may have to go over to the dark side and buy a PC

From the MES report am I right in saying that my ECU software is in fact as old as v23? Shoud I get the vehicle in to my local Fiat dealer as a matter of course to have this firmware upgraded to v32 and has anyone any idea as to what this might cost as I think they charge £120 + VAT per hour for any work!

Given my current error codes what analytics would I best be carrying out to determine what parts of the vehicle could be causing these errors and is it worth just renewing the Turbo Pressure Sensor given they are known to fail around the mileage of my engine?

Sorry for the long email but thought I would get everything out on the table and I am somehow looking forward to contributing to this group even though its a problem none of us wanted or expected to have when we purchased the twin egr engine - I am sure the MH will give me more pleasure than the negatives the engine may throw my way

 

[chumleywarner]

Sorry I forgot to mention that the vehicle does have a slight eratic idle and also when first setting off from cold I have noticed the engine surges and slows repeatedly when little throttle is being used and at a low speed - seems to be ok when warned up. Just thought this was worth mentioning if it helps diagnose the cause of my current ecu errors. Many thanks.

 

[kangexpress]

I don't think you're dealing with any of the issues mentioned in this thread at such low mileage.

The problems discussed here are related to the EGR system.

Your issue sounds more like a classic air leak in the turbocharger piping.

The turbocharger pipes can crack over time, leading to a possible air leak. This leak can cause a lean air-fuel mixture, which is likely why your DPF is now clogged due to the black smoke.

As long as the MIL (Malfunction Indicator Light) is on, the DPF regeneration process is deactivated. If you continue driving in this condition, your DPF may eventually become so clogged that even a forced regeneration won't be possible. At that point, you'll either need a new DPF or have the current one professionally cleaned, both of which require disassembling the DPF—a job that takes 6-8 hours of labor.

For these reasons, it’s not recommended to continue driving until the air leak issue is resolved.

The easiest solution is to have a mechanic use a smoke machine to detect any air leaks in the turbocharger piping.

Once the pipe is repaired or replaced, perform a forced regeneration, and you should be good to go.

 

[theoneandonly]

@chumleywarner in case things are misunderstood
i give my time for free, to help people.
your version is indeed 23
the lpegr cooler syndrome has been observed at your mileage.
get the pipework check out including the vacuum lines.
once you have a working multiecuscan setup i will guide you through some test . but now time for bed

 

[deejays]

@theoneandonly , the LP EGR temperature sensor is the wrong side of the cooler to add cleaner.
To attempt cleaner it has to be fed in at the flexi pipe that connects from the silencer.
I noted that the LP EGR opens on engine start up from cold, (I've only looked once).
I'm wondering if it's possible to undo the ring clamp at the silencer; part the flexi away ; blank the silencer tapping, with a cold engine start it and with MES showing the EGR opening spray a DPF cleaner up the flexi.
.
Alas I'm conjecturing from the armchair.....

@theoneandonly @kangexpress @Fredastaire Is it possible that kangexpress is onto something here? What about the following cleaning scenario?
Disconnect the exhaust entry to the LP EGR cooler from the bottom of the DPF from under the vehicle and block it temporarily with a large bung. From inside the cabin, with battery box removed, unscrew and set aside the LP EGR temp sensor. Fit tube to LP EGR temp sensor port and fill cooler with cleaning fluid and let soak for an extended period. Then remove bung allowing contents to pour out and follow up with introducing compressed air into tube fitted to temp sensor port to blow though and dry. Move over Fredastaire, room is required to share on that armchair..

 

[kangexpress]

@theoneandonly @kangexpress @Fredastaire Is it possible that kangexpress is onto something here? What about the following cleaning scenario?
Disconnect the exhaust entry to the LP EGR cooler from the bottom of the DPF from under the vehicle and block it temporarily with a large bung. From inside the cabin, with battery box removed, unscrew and set aside the LP EGR temp sensor. Fit tube to LP EGR temp sensor port and fill cooler with cleaning fluid and let soak for an extended period. Then remove bung allowing contents to pour out and follow up with introducing compressed air into tube fitted to temp sensor port to blow though and dry. Move over Fredastaire, room is required to share on that armchair..

Possible. But which cleaners or chemicals to use?

In my case. I've never had any luck with those dpf cleaners.

Finally I’ve had always to remove the dpf and let it professionally cleaned.

Youtube is full with dpf home diy dpf cleaning guys. But unfortunately never worked for me.

Anybody has ever successfully cleaned that kind of debris with a cleaner or chemical?

 

[deejays]

Possible. But which cleaners or chemicals to use?

In my case. I've never had any luck with those dpf cleaners.

Finally I’ve had always to remove the dpf and let it professionally cleaned.

Youtube is full with dpf home diy dpf cleaning guys. But unfortunately never worked for me.

Anybody has ever successfully cleaned that kind of debris with a cleaner or chemical?

This, courtesy of @Fredastaire from Page 16 of this long saga: