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

[aschoots]

Picked up the van today after a long stay at the dealer (beginning of November). Logged set #5 with MES to see how it performs now, file attached.
Reason for the long stay: Engine service (fresh oil and filter, brake fluid, etc), had the cracked DPF (very high soot particle count) fitted with new internals by local company (soot count now perfect), had ordered a Krosfou DPF at first but that did not fit correctly (still waiting for an RMA number & refund), fitted a clean -used- LP-EGR cooler (was completely blocked), fitted a revised Turbo (it had oil leakage into air side), had the injectors tested as MES showed up to +/- 3.5mm3/s correction.

Injectors – well over FIAT limit of +/- 2mm3/s. Strange, as injectors have been tested and are reported as OK…

LP-EGR system now works as intended / no more blocked LP-EGR cooler.

Temperatures around DPF / cat are OK.

DPF differential pressure looks OK.

Next planned step is to implement an ECU map mod that stops LP-EGR from working, so no more exhaust gas with a small (or bigger) amount of soot particles travelling back to the ‘clean’ inlet side of the engine. And -if it all works out- no more P401/402/238 limp mode errors.

This mod was done by @Poachersmoon (NZ), I’ve contacted Peter James Tuning (NZ), and worked with my local tuner Squadra (NL) to get prepared. Next steps are as follows:

• Read current ECU file (v32 with Squadra mod) using the Powergate 3+ tool.
• Download from Powergate to PC
• Send the file to Squadra (or Peter James Tuning if you live in NZ/AUS) for applying the LP-EGR modification
• Upload file from PC to Powergate
• Load from Powergate to ECU

Note: The LP-EGR mod requires to unplug the LP-EGR valve plug (I'll have to check if I can reach that).

Note: The Powergate holds the original downloaded file as well as one or more modded files, which enables the options to go back to original before MOT testing and to mod after.

Note: There is also a LP+HP EGR mod (disabling them both) available. I want to stay at least a bit compliant, so not doing that one.

I will post an update when there is something to report.

 

[theoneandonly]

@aschoots thanks for the update. Looks good, have you got a copy of the csv file? there's something id like to check.

 

[aschoots]

@theoneandonly here it is (mistakenly added the txt file earlier). Curious to what you will find.

 

[Niko94]

Hello guys...

After a clogged agr cooler was detected here from my runs with MES, i took the chance and had the complete egr system deactivated.

The vehicle drove very very well for 1500 kilometers. Afterwards, a trip to Serbia was on the agenda. After 350 kilometers, emergency run and no power.
Laptop and MES connected, P0237-61 and P0238-61.. Boost pressure sensor A circuit low and Boost pressure sensor A circuit high. Clearing error and not being able to continue, error always came back immediately. I then drove another 600km to my destination with emergency run.

In Serbia I talked to a mechanic. He told me that when deactivating the EGR system, it usually takes 1000 kilometers and then the particulate filter is clogged. He also said that cleaning DPF is only successful in 3 out of 20 vehicles. The DPF was now really clogged again. The bottom was black after starting the Ducato, the tissue test also showed completely black tissue. The mechanic cleaned the DPF for me again. After 220 kilometers again P0237-61, P0238-61. Another 700 kilometers with emergency run back to Austria.

I will do a few MES test runs the next days and check if both egr valves are closed. After successful 1500 kilometers, I honestly trusted that the EGR valves were certainly 100% closed and everything was programmed correctly. I also ran through a tank of system cleaner for the injectors, as mine didn't show the best values after the last few MES runs. Let's see if it did any good.

I'm going to take a look at the MAP sensor, mass air flow sensor and throttle body and clean it.

It's exactly the same as what @ER worker described in his post #517, only it's the other way around for me, EGR off but DPF clogged up again and again.

 

[theoneandonly]

If you look at poachers moon results the graphs show the egrs not working. So a run with mes will confirm things are working as they should.

 

[Fredastaire]

@Niko94 @theoneandonly , I wonder if the portion of software altered in the EGR delete has also deleted the 'regen' section?

 

[theoneandonly]

@Niko94 @theoneandonly , I wonder if the portion of software altered in the EGR delete has also deleted the 'regen' section?

The only way to confirm this with MES is to run my template 4 see attached photos. The egr opening or not can be seen by running egractual position both hp and lp. Injection qty(post) monitors the injection during regen, particle filter temperture can also be used to monitor a rgen. This would need to be monitored for at least 400/500 miles to prove regen is not occuring
see

DPF Regeneration

Ive been using Multiecuscan for a while now and along with my monthly blast up and down M1 have been doing health checks. Taking reading of various PIDs under standard conditions. I came across a measurement that tells you when regen is occuring...

www.fiatforum.com

 

[Niko94]

From the mechanic i drove 60 kilometers on the highway to my sleeping place. MES showed me clogging 86,..% and last regeneration 123km ago. From Serbia to me in Austria it was another 1080 kilometers. After switching off the engine at home, I opened MES straight away. Last regeneration 420 kilometers ago. Clogging was around 55%.

 

[theoneandonly]

This thread has been running for 2 years now, i have learned a lot from listening to people and analysing data. The techniques i use are quite simple and not Rocket (even though i used to work in the space industry).
The use of Multiecuscan to monitor/save data is crucial to my method. My method initialy is to compare a Golden sample and a "problem" sample . If data is available Now I go straight for the jugular of LPEGR actual position and temperature versus time then Differential dpf values, injector variance and probably done first the wiping of the exhaust pipe for soot.

Here are two examples of the same journey with an hot engine. I use the same graph settings for most examples to ease comparisson . The max and mean values are taken of the same data set normaly excluding the warmup period (or any anonamolous readings eg if sat in a layby) From these 2 results we can see a difference in the temperature.

Comparing this to first graph (same period 773 s) we can see LPEGR valve opening and closing more rapidly than on motorway.

An alternative approach is to look at Frequancy distributions or Histograms

A poorly system jumps between Max to min 4.7 to 0 mm, and a low temperature.

Graphs one and 3 are of the same time period (773s long). The difference is the period of being on or off. Motorway longer periods of on or off than the time. This and the luck of finding a 401 problem before the 401 occurred lead me to think of another way of looking at the data.
This is the end of this section

 

[theoneandonly]

I looked at the opening distance now time to look at opening period and its frequancy distribution. I picked non standard groups of 3,10,20,30,50,75,100,>100 seconds. The following are all my engine over the last 2 years and are in Chronological order (was supposed to be but looks like some copying errors 230208 is 8-feb-23). It is running perfectly well and shows no problem related to LPEGR. It does however have injector variance issues.

year 2022

So what does this show? Tell me.
I think if its a normal running engine it shows the naturaly acceptable variation that would be seen in the normal running of a Motorhome. THis could be short periods to a small number of longer periods.

 

[theoneandonly]

An example of a van throwing a 401 but showing LPEGR cooler temperature variation from good/ acceptable to poor not obvious.
Last graph is of after clean cooler fitted.

This is another example before and after clean LPEGR cooler fitted.

So where am i going with this?
Do my results show a good engine variation ? (i really need data from known good engines, anybody without problems within 30 miles of Northampton ? can i run tests on your engine?)
If they do and the last 2 are bad can we see a transition from good to blocked before a 401, and the need to remove the cooler again.
Can this method predict problems?
Mine currently does not have soot in the exhaust and the regen process is working well, but, its low mileage 12,000.

 

[NavNie]

Hello theoneandonly,

your question: So where am i going with this? Do my results show a good engine variation ?

My answer is no. Why ? The graphs only show the frequency of LPGR valve openings over time.
Even if the comparison is driven with the same driving profile (motorway, country road, city). The standard engine temperature must be reached,
as well as the climatic conditions: air temperature and air pressure.
Ultimately, all of the problems described here, began with the creation of soot, its filtering and its combustion in the particle filter.
A predictive diagnosis is possible based on the driving profile and the resulting cleaning processes in the particle filter.

That's just my 2 cents

greetings Klaus

 

[Jiwawa]

As someone who has experienced similar problems, I have read this thread with interest and (a little) understanding. I'm not technically or mechanically proficient but I do need advice.

My motorhome (2017 Fiat DUCATO Multijet 2.3 twin-EGR, non-adBlue) had glowplugs warning for quite some time but was starting well so I ignored it. Then I had problems of strangulated performance, as if it was driving with the handbrake on.

Fiat Professional diagnosed P0401-61 along with the fault codes below. Having cleared the faults they got the ones below reappearing (I've lifted the info from their jobsheet) -

EML LIGHT COMING ON, Carried out scan report. 4 codes
Vehicle showing active code
ECM P0683-11 Glow plug feedback - Circuit short to ground.
Stored codes, ECM EGR high pressure
ECM P0238-61 Turbo charger control positive drift
ECM P0236-7a Anomaly in air intake circuit (Fluid/seal)



The work they propose is as below. However, altho it mentions replacing the heat exchanger (cooler?) it doesn't specify that this is the LPEGR cooler which I understand from this thread is the big problem. I asked if it was LPEGR - he thought so but went to check. No, it's the HPEGR system. But he also talked about dropping the engine out to get at it; from my reading here, that points to the LPEGR, not the HPEGR. I can't even remember from the 40-odd pages here if the HPEGR has a cooler.

Can anyone advise please?

Work proposed:
STAGE TWO FOR EML LIGHT INSPECTION: Carried out inspections and Vehicle will require new glow plugs. Checked EGR system, removed and inspected, found valve and cooler blocked. Vehicle requires EGR cooler and valve. Turbo fault needs inspected when turbo removed.

R LAB 1625.00 S

Stage three repair.
Strip down and replace EGR Cooler and EGR valve. (Turbo unit needs inspected, may be faulty due to related fault code 'low pressure')

Replace 4 glow plugs.

M F5802823579 120103H GLOW PLUG 4.0 32.21 EACH 0.00 128.84 S

M F5802131785 N/STK HEAT EXCHANGER 1.0 310.35 EACH 0.00 310.35 S

M F0055279934 N/STK PIPE 1.0 118.78 EACH 0.00 118.78 S

M F0071796727 N/STK RECOND.D EGR V 1.0 249.25 EACH 0.00 249.25 S

Thank you.

 

[theoneandonly]

Hello theoneandonly,

your question: So where am i going with this? Do my results show a good engine variation ?

My answer is no. Why ? The graphs only show the frequency of LPGR valve openings over time.
Even if the comparison is driven with the same driving profile (motorway, country road, city). The standard engine temperature must be reached,
as well as the climatic conditions: air temperature and air pressure.
Ultimately, all of the problems described here, began with the creation of soot, its filtering and its combustion in the particle filter.
A predictive diagnosis is possible based on the driving profile and the resulting cleaning processes in the particle filter.

That's just my 2 cents

greetings Klaus

thanks for thinking and answering i think ive asked slightly the wrong question.

Do my results show a good engine variation ?

do my results show the variation of a good engine used in the normal manner? ie is what we should expect because of all the variables (that you mention). Looking at suffering engines they all have periods extending to 100 seconds and beyond. is this an indication of impending strangulation? Post Cooler clean they are all back to l0s or less.

A predictive diagnosis is possible based on the driving profile and the resulting cleaning processes in the particle filter.
the driving profile is typically unknown (i am using donated data). I am now trying to get data on the regen proccess. ie how much fuel injected, temperature profile and duration between regen (mileage). For predictive diagnosis i think i need to monitor the dpf temperature continuously to check that the dpf matrix does not exceed cracking temperature (Al2O3, alumina is typicaly fired to 950C so precise temperature of matrix not known (precise ceramic of matrix not known ). Catalytic converters are commonly made from ceramics containing a large proportion of synthetic cordierite.

Discussing ceramic DPF substrates - SIC vs cordierite - EEC

EEC has been manufacturing quality automotive products such as catalytic converters, diesel particulate filters, lambda sensors, exhausts, front pipes and brake pads, since 1997. We are the largest manufacturer of aftermarket catalytic converters in the UK with over 35 years experience, stocking...

eurocats.co.uk

Silicon carbide a much better material for the job as it is for other uses in electronics but 10 times cost of compitition.
Another prediction i'm interested in is for engines that have suffered "LPEGRcooler syndrome" that if the DPF is cracked and the cooler is replaced with a clean one, how long before blockage. Engines in this condition still pass the MOT emmission requirements so this is a acceptable repair.

 

[theoneandonly]

P0683​

Glow Plug Control Module to PCM Communication Circuit​

P0236 Normaly associated with turbo solenoid valve, vacuum feed or actuator on turbo.

​	P0238​	turbo pressure - low pressure,​
​	P0238​	Turbocharger Boost Sensor A Circuit High​

P0401 in association with 236,238 generaly a blocked LPEGR cooler
Low turbo pressure maybe the turbo solenoid or turbo actuator stuck or if a 150,180 stuck vanes on a variable vane turbo VVT

Is this a warrenty fix?
the glowplug issue , have they measured the resistance of individual glowplugs and confirmed each one is dead? the code to me indicates an electrical connection issue not 4 dead injectors.
M F5802131785 N/STK HEAT EXCHANGER 1.0 310.35 EACH 0.00 310.35 S
this looks to be same part number as my spare LPEGR cooler.

Check your exhaust with a kitchen roll wipe and inspect. clean or soot . it will be sooty @Fredastaire
Without live data this is the best i can do.

 

[Jiwawa]

Thank you for that @theoneandonly. No, it isn't a warranty job. The MH is 2017. Tho I would, apparently, have 2yrs' warranty on the work.

You say "M F5802131785 N/STK HEAT EXCHANGER 1.0 310.35 EACH 0.00 310.35 S
this looks to be same part number as my spare LPEGR cooler." - that's really what I want to hear as the whole thread points to that being the major issue; but he did tell me it was the HPEGR system.

I will have to check wihh him again, and also thanks for the pointers about the glowplugs.

Unfortunately I can't check the exhaust as it's not with me, but with FP.

 

[aschoots]

You say "M F5802131785 N/STK HEAT EXCHANGER 1.0 310.35 EACH 0.00 310.35 S
this looks to be same part number as my spare LPEGR cooler." - that's really what I want to hear as the whole thread points to that being the major issue; but he did tell me it was the HPEGR system.

My, and as I understand most other, dealers are able to change out the LP-EGR cooler and valve, and DPF without dropping the engine.

I believe the subframe (holding the front steering / wheels) is to be droppen, optimally keeping the brake- / steering fluid lines connected (which limits movement, so they would need to support the frame).

This is a lot less work than dropping the engine...

 

[NavNie]

Hallo theoneandonly,

your question: do my results show the variation of a good engine used in the normal manner?

And again my answer is no. The normal usage of the HPGR and LPGR Valve is to reduce the Nox values in the exhaust gas. So the valves are open as often as possible.
So the best compareable values are found, driving with constant speed using Cruise Control on flat ground.
The valves has to be closed during accleration, acclerated power driving uphill with constant speed, low engine temperature, DPF regeneration, long time idling...

your statement: the driving profile is typically unknown (i am using donated data).

Try to use the data which is readable from ECU, using AlfaObd, reading full engine status, you would be astonished, which data is available.
The difference to Mes is, that the evaluated data has to be interpreted in the correct way to got plausible answers for your questions.
One of the problems is, there is not much information about the measusred and stored values available.
In the data are stored Correction Values like the Injector Corrections, although available for the HPGR and LPGR Valve Values.
That values might be a sign for the correctness of the exhaust gas recirculation Process.

greetings Klaus

 

[Fredastaire]

Cooler removal- LP EGR
I've had mine changed at my local friendly garage and liased with them.
On a H ramp jack up body, remove front roadwheels. Undo bottom ball joints and track rod ends. Undo engine bottom locator strap. Undo steering rack subframe clamps. Undo the steering column inside the cab. Undo subframe, remove and set away on the floor. There are (I think) some heat shields on the steering rack to detach. The steering rack now dangles on its hydraulic hoses still fully pipes up.
Now you can reach the DPF for removal. The LP cooler is hidden behind the DPF.
I'm not aware of any of our series Ducatos needing a new LP EGR or it needing cleaning.
.
Do be aware that if multiecuscan shows the cooler to be blocked then that indicates the DPF has cracks.
.
Do be aware that a cracked DPF may have been caused / linked to wrecked/ faulty injectors.
.
I had my cooler changed 18 months back, im aware that my DPF is cracked so I'm unsure how long before the cooler re-blocks. Having a bi-annual cooler change is my choice to avoid the hefty cost of a replacement DPF.
.
If your garage says there is a problem with the HP EGR thats due to a software error which tells the mechanic that it's blocked. It's so misleading. Fiat must be earning Megabucks from selling new HP EGRs to replace perfectly good ones.
.
The miss leading bit is that when the LP cooler is blocked, the software asks the HP EGR to open up and compensate by letting more exhaust through, it's instruction to the HP is a crazy high stupid impossible air rate and because it cannot comply the software gives the 401 fault code which in turn tells you ' HP EGR blocked' when if course it isn't.

 

[theoneandonly]

@Jiwawa there is no reference to software version or even to the fiat service notes numberxxxx. If you read the whole 40 pages again you will find reference and @Fredastaire s statement about a 401 never (99%) means the hp valve is an issue. Is it manual or conformatic as that ecu will need a check or update as well. If you had acess to the van i would have suggested to some tests with multiecuscan. Typicaly injectors are also tested or replaced. Please note Fiat pro approach your money as an inexhautable supply if not reminded.