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

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

Two side comments.
There might be an error creeping in if any sensor is out of its intended range, one example, is the LP EGR temp sensor giving correct values?
Second what's the result if the intercooler is blocking with oil/ soot combination? It's relative straightforward to go underneath and after removing the clip, pulling the hose elbow off to take a look. When I had the cambelt changed, the mechanic spotted mine and reported it. (Flushed out with plenty of petrol)
According to some Fiat information I have read the ECU self-diagnostic system checks the signals coming from the sensors and compares them with the permitted limits. If outside these pre-set limits a fault code is generated to identify the wayward sensor. I have at least confirmed that when I was playing with the exhaust temperature sensors some time ago. Intercooler blocking would certainly reduce airflow and likely limit achievable boost pressure below target, but if that alone was the issue I do not think the Manifold Temperature would drop so low as in this example (it might even go high), and the LPEGR valve would likely be modulating nearer midrange if the cooler was clear.
 
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@deejays and @theoneandonly my csv files posted earlier were of my own choice, as I was trying to capture what was happening when the trouble code appeared and have chosen what might have been relevant. But anyway my van is back from the garage so today directly after work I’ve done some runs with those templates both @deejays and @theoneandonly were asking for, and I post them here. File number 1 is with the template @deejays proposed and file number 2 according to what I found in this forum that @theoneandonly proposed as template No5. Not a very long distance as my wife called me that the dinner was ready so I turned back home for this reason, hope you understand ;)
Some update, for those interested, as the Fiat garage has completed their test and their conclusion is: There is some deficiency in air intake and they could provoke faults (P0236 and P0238) driving about 70-80 km/h and trying to accelerate. There is not sufficient pressure from turbo or pressure is coming too late so the engine is not getting enough air. Two possible causes, first: turbine faulty or second: bugs in ECU’s software. Next step is changing the turbo. Estimated price for turbo (new) £3800 (converted from Swedish crowns) and 7-8hours labour on top. No promise that it solves the problem.

I have asked some questions, and in summary:
Me: Fault came for the first time after 50000km and software bug appeared first before software update and persisted after the software update to current version. Software update changed nothing - thus difficult to accept software fault as a reason
Garage: Well, that’s why turbo replacement is the first choice..
Me: is it possible that blocked LPEGR is restricting air intake and throwing codes?
Garage: No, our testing showed no problems in any other part of engine
Me: As there is soot in exhaust pipe it may happen that LPEGR is constricted or blocked as LPEGR takes exhaust gases after DPF
Garage: There is no excessive soot in the exhaust pipe in the van, just as much as they usually see on all other Ducatos…

Note: They do not know what Multiecuscan is. They use their own Fiat diagnostic gear.

Anyway, no choice on my part, as I already made some bookings for a summer trip to South France, I made an appointment for changing the turbo and it's scheduled in 2 weeks time. I think I’ll be doing some more test rides to gather recordings of diverse parameters before the turbo is changed to be able to find out if this is going to make any difference, I mean to compare with parameters after the change. Any ideas what kind of data I should be gathering in first place?
 

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Hej,

In the FCA Service News 10 023.19 shared in this thread (and perhaps in Downloads section also) there is a good illustration of normal vs abnormal result from the ”white cloth test”. See pages 4-5.
@MSjoberg I know, but "Fiat-not-so-Proffesional" as I'm calling them due to their inability to diagnose my issues, was not interested in looking any closer at this what a customer (me) is showing. They are convinced that they know best.
 
@jansla a slightly different tack with tonight graphs only looking at the Turbo but with other values superimposed. AS yet i have not done this with my engine results yet so no results to compare with. Its soon time for bed so I will leave it for others to comment. @deejays I think this was what you were suggesting in a previous post.
Just added the LPEGR graph
Engine J  LPEGR 250515-File 2.jpg


Engine J  Turbo pressure 250515-File 2-1.jpgEngine J  Turbo pressure 250515-File 2-2.jpgEngine J  Turbo pressure 250515-File 2-3.jpgEngine J  Turbo pressure 250515-File 2-4.jpgEngine J  Turbo pressure 250515-File 2-5.jpgEngine J  Turbo pressure 250515-File 2-6.jpgEngine J  Turbo pressure 250515-File 2-7.jpgEngine J  Turbo pressure 250515-File 2-8.jpgEngine J  Turbo pressure 250515-File 2-9.jpgEngine J  Turbo pressure 250515-File 2-11.jpgEngine J  Turbo pressure 250515-File 2-12.jpg
 

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@deejays and @theoneandonly my csv files posted earlier were of my own choice, as I was trying to capture what was happening when the trouble code appeared and have chosen what might have been relevant. But anyway my van is back from the garage so today directly after work I’ve done some runs with those templates both @deejays and @theoneandonly were asking for, and I post them here. File number 1 is with the template @deejays proposed and file number 2 according to what I found in this forum that @theoneandonly proposed as template No5. Not a very long distance as my wife called me that the dinner was ready so I turned back home for this reason, hope you understand ;)
Some update, for those interested, as the Fiat garage has completed their test and their conclusion is: There is some deficiency in air intake and they could provoke faults (P0236 and P0238) driving about 70-80 km/h and trying to accelerate. There is not sufficient pressure from turbo or pressure is coming too late so the engine is not getting enough air. Two possible causes, first: turbine faulty or second: bugs in ECU’s software. Next step is changing the turbo. Estimated price for turbo (new) £3800 (converted from Swedish crowns) and 7-8hours labour on top. No promise that it solves the problem.

I have asked some questions, and in summary:
Me: Fault came for the first time after 50000km and software bug appeared first before software update and persisted after the software update to current version. Software update changed nothing - thus difficult to accept software fault as a reason
Garage: Well, that’s why turbo replacement is the first choice..
Me: is it possible that blocked LPEGR is restricting air intake and throwing codes?
Garage: No, our testing showed no problems in any other part of engine
Me: As there is soot in exhaust pipe it may happen that LPEGR is constricted or blocked as LPEGR takes exhaust gases after DPF
Garage: There is no excessive soot in the exhaust pipe in the van, just as much as they usually see on all other Ducatos…

Note: They do not know what Multiecuscan is. They use their own Fiat diagnostic gear.

Anyway, no choice on my part, as I already made some bookings for a summer trip to South France, I made an appointment for changing the turbo and it's scheduled in 2 weeks time. I think I’ll be doing some more test rides to gather recordings of diverse parameters before the turbo is changed to be able to find out if this is going to make any difference, I mean to compare with parameters after the change. Any ideas what kind of data I should be gathering in first place?
Hi @jansla , Just a quick reply. Am I correct in assuming that your engine is a 130HP version and not a 150HP or 180HP? Can you please confirm? One other quick note: I see that you ran the template I suggested first, then quickly stopped the vehicle and ran the other template. It is a shame you did not stick to the one template and continue driving as it would appear that for the significant warmed state of engine that a DPF regen (burn) was initiated and makes the collected data not all that valid as the engine parameters change during that process. It would appear that you stopped the vehicle just near the completion of the burn process (you may have interrupted it). Still, some meaningful data can be collected, but the other template is missing the inlet manifold temperature (critical) so that is lost. The other issues I see with the other template is wasted data slots. For example, the four injector corrections are only valid for a warm engine at idle only, not during any other part of the test. The engine temp signal (V) is also a wasted slot. And unless someone can explain to me what the next two mean, then I consider they are two more wasted slots: HPEGR and LPEGR valve opening %. The description of these two parameters in MES is confusing at best. I am guessing they may represent the duty cycle of the stepper motor drive signal, but who knows and what is the relevance in this instance? @theoneandonly have you any idea what they represent? I will look at the data in detail later as I have many other pressing things to attend to right now. If the garage is looking at replacing the turbo, I reckon before that I would be asking them to at least stick a borescope up the LPEGR cooler pipe to have a look at the state of the actual cooler.
 
@jansla @deejays the template used is not what is required now. I also dont understand the use of % openning and why others were used. @jansla Please use the template given by @deejays. How will a stuck VVT show itself? After this next test I would suggest a full throttle pull test but lets not confuse things @jansla Please use the template given by @deejays and confirm if the motor is a 130 or not (150,180)
 
@deejays it was not wise of me to record two different patterns, but the idea was to record one according to yours and one according to theoneandonly’s template No5 which I found in this thread. I will record some more today after work with the set of deejays parameters all the way.

My van was 130HP from factory but upgraded to higher power with remapping done 2 or 3 weeks after delivery with this https://en.bsr.se/tuning-kits/Motorhome/Fiat/2018/Ducato/2.3-130Hp-MultiJet-Euro6
 
@deejays it was not wise of me to record two different patterns, but the idea was to record one according to yours and one according to theoneandonly’s template No5 which I found in this thread. I will record some more today after work with the set of deejays parameters all the way.

My van was 130HP from factory but upgraded to higher power with remapping done 2 or 3 weeks after delivery with this https://en.bsr.se/tuning-kits/Motorhome/Fiat/2018/Ducato/2.3-130Hp-MultiJet-Euro6
Just had a quick read before going out. Can you easily revert to the standard, did you have v32 upgrade after the reprogram?
 
@theoneandonly v32 upgrade was done lately, (last year or just before) and from the beginning I was on tuned version. The first time when problem came was after driving during several years (5) on tuned but old software. Then upgrade to v32 but no effect, besides that last summer I've done 5000km with no faults but in September problems came back. Attaching csv from todays ride, hope I've chosen right settings proposed by @deejays Today second part (half way), going back home was against rather strong wind blowing about 55km/h (today and yesterday no faults)
 

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it was 34km, exactly the same route as previously recorded on files FESExp_250515..., the temperature gauge reached usual position after about 3km. The csv file shows that the engine got to 80C at the row 414, and the time stamp 556s, so why 33C?
 
it was 34km, exactly the same route as previously recorded on files FESExp_250515..., the temperature gauge reached usual position after about 3km. The csv file shows that the engine got to 80C at the row 414, and the time stamp 556s, so why 33C?
@jansla I think that perhaps MAP temp was mistakenly read as Engine temp by @theoneandonly . The Engine temp is fine, but I have my doubts about the MAP temp. Report about to be uploaded.
 
@theoneandonly v32 upgrade was done lately, (last year or just before) and from the beginning I was on tuned version. The first time when problem came was after driving during several years (5) on tuned but old software. Then upgrade to v32 but no effect, besides that last summer I've done 5000km with no faults but in September problems came back. Attaching csv from todays ride, hope I've chosen right settings proposed by @deejays Today second part (half way), going back home was against rather strong wind blowing about 55km/h (today and yesterday no faults)
@jansla , thank you for confirming your engine is (or was!) 130HP. The reason I knew that was because two parameters (Turbo Control Position, desired and actual) are showing null result.

The 130HP has a wastegate and not a VGT/VVT as fitted to the 150HP and 180HP versions. The VGT/VVT turbo has positional feedback whereas the wastegate version does not.

The upside is you have two more MES parameter slots you can put to good use instead; the downside is you have no idea if the turbo is following the requested commands of the Turbo Solenoid.

Some 40 to 50 years ago I spent many hundreds of hours modifying Lotus Twin Cam engines to develop considerably more power for racing purposes. But there is no way I would even consider modifying the programming of any of the software in any vehicle – particularly this engine. Both Magneti Marelli and FIAT have vast resources and talent and many years of development experience to deliver this vehicle. To then think that some relatively tin-pot company knows better, I believe is a folly. If more power and torque was the name of the game, why not buy the higher-powered version in the first place? That said, this issue may have happened regardless – so don’t feel too bad about it.

Understanding that the ECU was modified early on, over the original SW V24, then having the ECU updated to V32, can one be sure what the current state of programming the ECU is I wonder?

Having said all that that, let’s move on and have a look at the data.

Fuel Quantity, Air Quantity, HPEGR and LPEGR all seem to line up as to Actual Position achieving the Desired/Target position, so those actuators at least can be confirmed to be following the directions of the ECU commands. I won’t display the graphs here – I encourage you to have a look yourself to confirm.

The Atmospheric Pressure and MAF Air Temperature would also appear to be reporting correctly, although you can confirm that precisely yourself.

The Boost Pressure is an issue across the Time, Pressure, RPM, and Speed Domain. Following are two graphs showing first, Time domain, then Pressure domain. RPM and Speed range require active toggling to view so are not shown here, but you can do so yourself if you want to view it. The boost pressure is down some 10% to 12% of where it should be (but again, what program is it responding to?).

Time Domain:
1747455924806.png


Pressure Domain:
1747455978849.png


The question of course is, what is causing this discrepancy? It could be a failing turbo, it could also be a near blocked LPEGR cooler, it also could be made worse by a congested intercooler. Understanding the turbo vacuum solenoid and associated components as well as the MAP sensor have been checked and or replaced and confirmed to be working correctly then those components will not be part of this consideration.

Let’s move onto the elephant in the room, shall we?

The LPEGR valve is rarely observed to be modulating linearly and when it does, it is at the high (open) end of its range. Coincident with this, the recorded LPEGR Temperature is high and judging by the “reference” of my engine data, the MAP Air Temperature should be in the range of 50C to 70C but instead is hovering much lower at approximately 30C. If the LPEGR valve is wide open for most of the time with a high LPEGR Gas temperature, then why is the MAP Temperature so low? One explanation is that the LPEGR cooler is significantly blocked, but not totally, thus allowing some high temperature gas to flow, but not enough to raise the MAP temperature. (But this is not the same engine as the “reference” and has had modifications applied to the ECU). The MAP temperature sensor can be confirmed as working correctly because it can be observed that when the HPEGR valve opens it causes the MAP Temperature to rise to the expected temperature range. So, perhaps a blocking LPEGR cooler then? Or perhaps a failing turbo? Or both? Or something else?

If the fault is intermittent, then it may pay dividends to have a close read of the following link as it describes an interesting and similar issue for the same 130HP engine:

(But it does not make any reference to the implicated low temperature of the Inlet Manifold).

https://www.picoauto.com/library/ca...th-turbo-under-boost-and-air-flow-meter-drift

If this was my engine and my wallet, before I handed over any more money for any more parts I would want to visually confirm the condition of the internal health of the LPEGR cooler, the intercooler, and a full check of the relevant wiring as per the above link and perhaps even a test as per the link.
One thing to keep in mind. For some years you have had an exhaust pipe with significant black soot. You cannot find even one speck inside the exhaust pipe of my vehicle. If there is soot in this engine exhaust pipe, then the DPF has failed. Eventually the LPEGR cooler will block as a result. This is documented throughout this brilliant thread created by @Fredastaire .

This is an excellent opportunity for anyone reading this who owns a healthy 130HP engine to perhaps offer a sample CSV file with the parameters that are being measured in this case.

1747456048304.png
 
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Dear @deejays , I am so incredibly grateful for your explanations, time and commitment to solving my problem. This last analysis is a masterpiece and you have no idea how much you have contributed to my much better understanding of this whole issue. I fully agree with you that the thread led by @Fredastaire together with the valuable contribution of @theoneandonly was, is and will be helpful for all those who want to understand it better before they are buried under an avalanche of spare parts replaced unnecessarily. For me, there has always been only one order of things: first diagnosis, then treatment. If I could look into the turbine or LPEGR, I would unscrew them myself and see what is going on there, but I can't remove the engine from the Ducato in my conditions.
I admit that I wondered why you wanted me to record Turbo Control Position, desired and actual when there are only zeros. But now it is quite clear and I had no idea that these other models have different turbines.
I fully agree that Magnetti Marelli and others have a lot of experience and software modifications can end-up badly. However, in my case it turned out that (I will tell you about it on another occasion) we bought 130HP. We drive quite a lot in the Alps and this is definitely not enough. I know that the Swedish company BSR has good engineers, they have a big contribution to the Koenigsegg's engine design. What's more, the local Motorhome dealers officially do upgrade tuning in cooperation with BSR. So I assumed that if it has been used quite widely for a long time, any shortcomings should have become apparent. I took this risk and I do not regret it! There is still a possibility that tuning is a part of my problems, I am aware of that.

Last year I came across this case description (your link on picoauto.com) from January 2019 and there were only exactly these two error codes as in my case. Inspired by this description I bought an oscilloscope (Pico, the simplest one) and I looked closely at the cables under the ABS pump, I tried to start and looked if the oscilloscope showed any disturbances but nothing. Probably like in most Ducatos, in my case the rain from the windscreen is also maliciously directed towards the ECU, ABS area so I hoped I would find something. I did not cut the cables completely but it looked good. I also did not see any relationship with the amount of moisture or rain when it comes to my sporadic errors. There is rather a relationship with the engine temperature in such a way that if I remember correctly, the errors almost always appeared just before or just after the engine reached operating temperature. Almost always about 5 km after starting. If the error does not appear in the first 10 km after stopping, then you can drive all day. That is why my assumption is now a waste-gate leak. It may be that it has a leak and sometimes it closes better and sometimes worse. In two weeks I will be able to see it - maybe? That the LPEGR is clogged, I agree, there are many indications of this, but since for 2-3 years I have had too low boost pressure, the combustion process does not proceed as expected and produces too much soot.
Btw do you know how the LPEGR vale looks like? Is it cutting off the fresh air from filter completely when it engages, or it only connects with exhaust letting exhaust in together with fresh air?

Thank you very much for your analysis once again!
 
Dear @deejays , I am so incredibly grateful for your explanations, time and commitment to solving my problem. This last analysis is a masterpiece and you have no idea how much you have contributed to my much better understanding of this whole issue. I fully agree with you that the thread led by @Fredastaire together with the valuable contribution of @theoneandonly was, is and will be helpful for all those who want to understand it better before they are buried under an avalanche of spare parts replaced unnecessarily. For me, there has always been only one order of things: first diagnosis, then treatment. If I could look into the turbine or LPEGR, I would unscrew them myself and see what is going on there, but I can't remove the engine from the Ducato in my conditions.
I admit that I wondered why you wanted me to record Turbo Control Position, desired and actual when there are only zeros. But now it is quite clear and I had no idea that these other models have different turbines.
I fully agree that Magnetti Marelli and others have a lot of experience and software modifications can end-up badly. However, in my case it turned out that (I will tell you about it on another occasion) we bought 130HP. We drive quite a lot in the Alps and this is definitely not enough. I know that the Swedish company BSR has good engineers, they have a big contribution to the Koenigsegg's engine design. What's more, the local Motorhome dealers officially do upgrade tuning in cooperation with BSR. So I assumed that if it has been used quite widely for a long time, any shortcomings should have become apparent. I took this risk and I do not regret it! There is still a possibility that tuning is a part of my problems, I am aware of that.

Last year I came across this case description (your link on picoauto.com) from January 2019 and there were only exactly these two error codes as in my case. Inspired by this description I bought an oscilloscope (Pico, the simplest one) and I looked closely at the cables under the ABS pump, I tried to start and looked if the oscilloscope showed any disturbances but nothing. Probably like in most Ducatos, in my case the rain from the windscreen is also maliciously directed towards the ECU, ABS area so I hoped I would find something. I did not cut the cables completely but it looked good. I also did not see any relationship with the amount of moisture or rain when it comes to my sporadic errors. There is rather a relationship with the engine temperature in such a way that if I remember correctly, the errors almost always appeared just before or just after the engine reached operating temperature. Almost always about 5 km after starting. If the error does not appear in the first 10 km after stopping, then you can drive all day. That is why my assumption is now a waste-gate leak. It may be that it has a leak and sometimes it closes better and sometimes worse. In two weeks I will be able to see it - maybe? That the LPEGR is clogged, I agree, there are many indications of this, but since for 2-3 years I have had too low boost pressure, the combustion process does not proceed as expected and produces too much soot.
Btw do you know how the LPEGR vale looks like? Is it cutting off the fresh air from filter completely when it engages, or it only connects with exhaust letting exhaust in together with fresh air?

Thank you very much for your analysis once again!
Like you, I have learned from this thread, and am still learning. I suggest that @Fredastaire may be able to refresh the information he has on the relationship of the LPEGR valve - it might be a good time to do so. Failing that, there is a photograph and sketch a long way back in this thread. I have not physically had one to look at - Fredastaire has. As fredastaire has already indicated, it is not to difficult to check the intercooler. To check the LPEGR cooler would require undoing the flex hose clamp from the DPF to obtain access to insert a borescope up the pipe to the cooler. It is something that the garage should probably look at as a pre-emptive to any further works. I will post a revised parameter template shortly.

EDIT: According to the very early explanation, once the LPEGR opens around halfway, it begins to shut off the incoming fresh filtered air and continues to do so until it is fully open to the recycled gas and almost fully shuts off the fresh air - which could result in low boost pressure. (It is a three way valve).
 
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@jansla @deejays , I confirm I bought an LP EGR off eBay to enable understanding. I took the cover off. Inside is a single 12 v motor via gearing drives the EGR flap shaft. Direct mounted on the flap shaft is a cam plate. Look at my drawing, there is a shaped internal slot with a roller follower. The roller is on an arm from the butterfly axle/ shaft. So when the EGR flap is driven say to 50%; the butterfly is inactive. Over 50% then the camplate moves the roller follower to then close the fresh air butterfly.
The EGR was rusty inside (from their cleaning it) so it went back for refund.
Although I operated it by hand I cannot recall definitive but I think it closes the butterfly 98%.i said 98% because memory tells me that the butterfly hadn't marked the inside of the casting so wasn't touching.
I was thinking about making a new camplate fir testing in mine, however I've yet to figure out how to remove the LP EGR without first removing the DPF, alas I'm not fit for mega sub frame removal to access the DPF .
As said, on earlier page I did add photos of the LP EGR, do also take note that there are at least two models, I suspect the 150/180 turbo inlet attachment is different.
I have perused cutting an access porthole in the engine bulkhead to enable undoing the EGR cover plate - whilst drastic it mustn't be entirely set aside.
 

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Hi @jansla , I wish to share with you some further snapshots of my engine. This shows pertinent data just at the beginning of a DPF regen phase (burn) and I consider this valuable to further demonstrate what may be the fundamental issue with your engine. Now, they are different engines, but one would think that there would be very similar parameters and responses.

The reason I have picked the beginning of the Regen phase is to demonstrate what happens to the Inlet Manifold Temperature when both the HPEGR and LPEGR valves are fully shut off, as is what happens during the DPF Regen phase.

This is an equivalent situation that would occur if an LPEGR cooler was blocked (or blocking) except the engine is not choked for fresh air. So far as the inlet system goes, it is normal except there is no EGR.

The following graphs are all the identical snapshot. Graph No. 1 is an overview with a vertical line drawn in the middle to show parameter values on the graph.

Graphs No. 2 to No. 4 are identical with three parameters removed to allow scale change for detail and decluttering the graphs.

Graph No. 2 - the vertical line drawn just prior to Regen showing the LPEGR valve modulating, near full open, LPEGR Cooler Temperature high, and Inlet Manifold Temperature in the normal operating range at 66C.

Graph No. 3 – The vertical line drawn approximately 115 seconds later after both EGR valves have shut, showing the fall of the LPEGR Cooler Temperature as there is now no gas flow, and also the rapid fall of the Inlet Manifold Temperature down to a very much stable 39C give or take a few degrees purely dependant on throttle opening and thus engine loading, power, boost etc. The fall of the LPEGR Temperature is not of consequence here. What is of consequence is the fact the Inlet Manifold Temperature is regulating in the very similar range that your engine is exhibiting with a fully open LPEGR valve and a high LPEGR Cooler Temperature.

Surely this points towards the issue being a blocked, or nearly blocked cooler does it not?

Graph No. 4 – The vertical line drawn later again, to demonstrate the area where the Inlet Manifold Temperature is influenced by the throttle opening (loading) of the engine.

As has been documented, with the LPEGR near full open, and a blocked or near blocked cooler, then the engine becomes strangled as the LPEGR valve restricts the fresh air supply to the engine. This in turn would lead to low boost levels as the air volume is not available for the turbo to boost.

If the waste-gate was leaky, then one would think that that amount of leak would be reasonably constant and the effect of that on the total boost amount should fall off as the turbo is called upon to provide more and more boost. But it is not. The actual boost is some 10% to 12% down on the required boost across the range. The other issue we face is we are trying to come to grips with how all the various sensors and actuators are integrated and all the various and interrelated feedback loops. However, I suspect the only sensor that controls the boost amount is the MAP sensor – and that has already been replaced. The ECU is reporting that the measured boost is lower than it should be according to the lookup tables written in the software for the given operating conditions. The boost is down across the entire range. If the turbo and the associated vacuum drive components can achieve high enough boost to drive the vehicle at 100kph, then it has sufficient operating range and capability to provide the correct small amount of boost at say, 30kph. But in this case, it doesn’t. I would think that if the MAP sensor is reporting low boost at 30kph, then there is more than enough range to drive the turbo to boost to the correct amount. But not if the air supply is not there.

If I was a gambling man, I would bet the house………., but I am not a gambling man. If I was an engineering man (which I am), I would think the DPF has been broken for some time (witness very sooty exhaust pipe) and the LPEGR Cooler is likely near blocked. If it is something else altogether, then hopefully your garage can find it and fix it; but if it was my vehicle, I would want to at least have the state of the cooler checked before I did anything else.

One thing I have noticed in this thread is that the documented engines with the blocked cooler issue had reported low Inlet Manifold temperatures around the same temperature.

@theoneandonly , can you add any further information regarding the Inlet Manifold Temperature with respect to a good working engine vs blocked cooler syndrome?


Graph No. 1: DPF Regen (beginning) overview, including Vehicle Speed, RPM and Particle Filter Temp. These three parameters will be removed to display detail in the graphs after this one.
1747538357670.png



Graph No. 2: Identical snapshot as above, with scale changed to show detail and vertical line reference shifted to beginning to show parameter values at start.
1747538412464.png



Graph No. 3: As above with vertical line reference shifted to show parameter values at different point on graph.
1747538473331.png



Graph No. 4: As above with vertical line reference shifted to show parameter values at different point on graph.
1747538524595.png
 
@deejays
yes, your analysis and explanation are coherent and I have to admit that they are convincing. I hope something turns out, they have set a date for starting the turbo replacement for Wednesday, May 28th. I know that this is probably another unnecessary part replaced, but another Fiat Professional is nearly a two-hour drive each way, so I am practically doomed to the local garage. I hope they check the LPEGR and its cooler when they get there...
 
@deejays
yes, your analysis and explanation are coherent and I have to admit that they are convincing. I hope something turns out, they have set a date for starting the turbo replacement for Wednesday, May 28th. I know that this is probably another unnecessary part replaced, but another Fiat Professional is nearly a two-hour drive each way, so I am practically doomed to the local garage. I hope they check the LPEGR and its cooler when they get there...
I would be making sure they do check it at a bare minimum. If it is blocked, then that is likely the issue and will need replacing. You would then also need to consider the future and think about replacing the DPF at the same time perhaps?
 
Revised/refined suggested parameters for both 130HP and 150/180HP Engines variant:

Refined Parameters for 130HP Engine:
1747541063883.png



Refined Parameters for 150HP/180HP Engine:
1747541117680.png
 
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