Technical Fault code p0238 boost sensor.

[Dave Tring]

I have a 2015 2.3 150 x290 maxi ducato motorhome a continued problem with code p0238 A circuit high. On previous advice from the original brakedown and code read by the AA man who was very informative and through. I have changed this sensor twice now both lasted approximately two to three thousand miles and I have the same problem eml limp mode and on reading the the code with my Autel reader P0238 circuit A high
appears. This always seems to happen when I have been driving two or three miles from cold and under load uphill. When this happens I stop and delete the code and all is ok maybe for 3 or 4 hundred miles.
Any suggestions on how I can fix this problem? I don’t really want to throw money at Fiat dealers because I have no confidence in them from past experience.
Advice please.
Regards.Dave Tring.

 

[Cmstewart]

I have same problem with 2010 2.3 multi -jet ! Changed cam sensor , wiring loom checked, new cam belt & timing checked & ecu tested and ok .Still cam sensor fault & goes into limp mode ! HELP

 

[Dave Tring]

I have same problem with 2010 2.3 multi -jet ! Changed cam sensor , wiring loom checked, new cam belt & timing checked & ecu tested and ok .Still cam sensor fault & goes into limp mode ! HELP

Hi my problem is with turbo boost sensor on a later engine model, 2015 onwards (x290)
But if I come across a solution I will post it on here , it could be the same simple fix you never know. Have you added a new second earth strap from the engine or gearbox to the chassis? This can fix a lot of stupid problems.
Dave Tring.

 

[theoneandonly]

Turbo solenoid test

This discusses the option to test the (turbo solenoid)boost valve in MultiEcuScan.

www.fiatforum.com

First things first With multiecuscan you can do a lot more than just read error codes.
as well as above test i would do a a "wide open throttle pull" test from a warm engine live data read "boost pressure" and "desired boost pressure" and RPM. then create a graph.(also actual, desired turbo position) if you want get the raw data publish here and i will look at the data.
to do test
1 warm up engine
2 get a nice empty road and accelarate rapidly
3 in 3rd gear full throttle accelaration until max (sensible revs) (or 2nd if cant find a suitable road)
4 foot off until revs idle then repeat.

 

[cornishsurfcampers]

I’m currently experiencing this exact problem with my 2017 130 Ducato. 100k miles
Limp mode almost every time I use it as it comes up to operating temp, a quick ign off/on and we’re away again just with the EML showing.
The codes I get are mainly P0401 which is EGR level not as expected, but also P0238 as above.. so I decided to replace the MAP (manifold absolute pressure) sensor.
That is a bit of an awkward thing to get to (a good 30 mins + of stripping bits off until you can see it… then the bloody fixing screw sheared in half! And I couldn’t get the broken half out (it sheared again at the base while I tried)
So I had to bodge the new MAP Sensor in with JB weld (as the only other option would be to replace the entire plastic inlet manifold)..

Anyway I’m still getting the errors!.. granted seemingly less frequently, but often enough to be annoying.

My next step is to clean out (or possibly remove) the EGR

This is a pic of the sheared sensor locating screw

 

[theoneandonly]

I’m currently experiencing this exact problem with my 2017 130 Ducato. 100k miles
Limp mode almost every time I use it as it comes up to operating temp, a quick ign off/on and we’re away again just with the EML showing.
The codes I get are mainly P0401 which is EGR level not as expected, but also P0238 as above.. so I decided to replace the MAP (manifold absolute pressure) sensor.
That is a bit of an awkward thing to get to (a good 30 mins + of stripping bits off until you can see it… then the bloody fixing screw sheared in half! And I couldn’t get the broken half out (it sheared again at the base while I tried)
So I had to bodge the new MAP Sensor in with JB weld (as the only other option would be to replace the entire plastic inlet manifold)..

Anyway I’m still getting the errors!.. granted seemingly less frequently, but often enough to be annoying.

My next step is to clean out (or possibly remove) the EGR

This is a pic of the sheared sensor locating screw

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

Have a read of this guide. I suspect you are the victim of twin egr syndrome.
Have you got a copy of multiecuscan? if not that is the first thing you need to do. Then do a run of live data and i will analize the data for you .
Next get a kitchen roll and then wipe out the exhaust pipe. and post a picture here.
Once we are sure of the problem we can then advise the best way forward.

by they way read this

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

26,190 miles, 2017, Comfortmatic, v32 software. This is the first time I've been brave enough to wipe the exhaust. Super diesel with Millers.

www.fiatforum.com

 

[cornishsurfcampers]

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

Have a read of this guide. I suspect you are the victim of twin egr syndrome.
Have you got a copy of multiecuscan? if not that is the first thing you need to do. Then do a run of live data and i will analize the data for you .
Next get a kitchen roll and then wipe out the exhaust pipe. and post a picture here.
Once we are sure of the problem we can then advise the best way forward.

by they way read this

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

26,190 miles, 2017, Comfortmatic, v32 software. This is the first time I've been brave enough to wipe the exhaust. Super diesel with Millers.

www.fiatforum.com

Thats great info, thanks for that.
I dont have multiscan but should probably get it, I have Vdash for my Volvo and its proven useful.
You sound very knowledgeable about these engines,. If I just have the EGR mapped out will this (likely) stop my problems?
I have noticed that the engine can be mildly erratic, for E.G. getting mild surges of acceleration when I haven't changed the throttle position

 

[theoneandonly]

Thats great info, thanks for that.
I dont have multiscan but should probably get it, I have Vdash for my Volvo and its proven useful.
You sound very knowledgeable about these engines,. If I just have the EGR mapped out will this (likely) stop my problems?
I have noticed that the engine can be mildly erratic, for E.G. getting mild surges of acceleration when I haven't changed the throttle position

Currently i wouldnt suggest deleting egrs or dpf.
HAs the van been to a Fiat pro dealer for servicing?
If not the ecu will need updating. We also need to know the current software version. This is easily found with multiecuscan. What month was it registered or left the factory?

 

[Fredastaire]

@cornishsurfcampers please please talk direct with @theoneandonly he is now probably our world expert on data reading and fault analysis on our Euro 6 non Adblue twin EGR Ducatos for these P0401 problems. I'm the owner of one of these, we talk regularly and help people all over the world with our spec vans. I've been through this from 3 years back. There is a posting on the forum now on 50 plus pages where I have had major input. If you read all 50 pages you will have the complete story, however at this point I recommend you start simply buy buying Multiecuscan from Gendan UK together with their leads then @theoneandonly will talk you through setting parameters to search and record them, then email him the file.
99.999% you do NOT have an EGR problem, it will be a blocked LP EGR cooler.
We believe Fiat have errors in their installed software where engine faults are defined as HP EGR, which it is not, it leads everybody up the garden path to buy a new HP EGR.
Please trust @theoneandonly, we are here to help.

 

[cornishsurfcampers]

@cornishsurfcampers please please talk direct with @theoneandonly he is now probably our world expert on data reading and fault analysis on our Euro 6 non Adblue twin EGR Ducatos for these P0401 problems. I'm the owner of one of these, we talk regularly and help people all over the world with our spec vans. I've been through this from 3 years back. There is a posting on the forum now on 50 plus pages where I have had major input. If you read all 50 pages you will have the complete story, however at this point I recommend you start simply buy buying Multiecuscan from Gendan UK together with their leads then @theoneandonly will talk you through setting parameters to search and record them, then email him the file.
99.999% you do NOT have an EGR problem, it will be a blocked LP EGR cooler.
We believe Fiat have errors in their installed software where engine faults are defined as HP EGR, which it is not, it leads everybody up the garden path to buy a new HP EGR.
Please trust @theoneandonly, we are here to help.

Well after an en-heartened plea like that, how can I not??!!
Its good to know that this is a common fault. (I think)
I have now had the van for about 2 years and it came with little in the way if service history, the Gentleman who had it before me had it serviced at a non-dealer garage, and from what I can see they weren’t great (for starters the undertrays are missing) so I doubt its been to Fiat dealer for a long while… not that I would trust a main dealer to be fair.
It did go in for a recall as soon as I bought it, though I do not know what it was for, and the dealer couldn’t/wouldnt tell me .

 

[theoneandonly]

Just quick response , mANY/most dUcatos did not have full under trays. Many Motorhomes including mine only have the belt side cover. Full trays are available from EBAY.

 

[cornishsurfcampers]

Just quick response , mANY/most dUcatos did not have full under trays. Many Motorhomes including mine only have the belt side cover. Full trays are available from EBAY.

If it is at all possible, I would very much appreciate the opportunity to talk with you on the phone about this issue we are having.
I’m not that good on forums and cannot see a way to DM you

 

[cornishsurfcampers]

Currently i wouldnt suggest deleting egrs or dpf.
HAs the van been to a Fiat pro dealer for servicing?
If not the ecu will need updating. We also need to know the current software version. This is easily found with multiecuscan. What month was it registered or left the factory?

It was registered in the UK on

Currently i wouldnt suggest deleting egrs or dpf.
HAs the van been to a Fiat pro dealer for servicing?
If not the ecu will need updating. We also need to know the current software version. This is easily found with multiecuscan. What month was it registered or left the factory?

it was registered in the UK on 31st March 2017

 

[theoneandonly]

There were 3 recalls for a 2017 check if they were done by using

Check if a vehicle, part or accessory has been recalled

Check if a vehicle model, part or accessory has been recalled because of a fault in how it was made

www.gov.uk

to get multiecuscan i reccomend gendan

Gendan Automotive Products :: MultiECUScan Package Chooser

 

[cornishsurfcampers]

There were 3 recalls for a 2017 check if they were done by using

Check if a vehicle, part or accessory has been recalled

Check if a vehicle model, part or accessory has been recalled because of a fault in how it was made

www.gov.uk

to get multiecuscan i reccomend gendan

Gendan Automotive Products :: MultiECUScan Package Chooser

I checked that when buying it, and thats when it said there was a recall.
Since having it done at the Fiat Commercial place in Truro there have been no more outstanding recalls showing

 

[jackwhoo]

I have a 2015 2.3 150 x290 maxi ducato motorhome a continued problem with code p0238 A circuit high. On previous advice from the original brakedown and code read by the AA man who was very informative and through. I have changed this sensor twice now both lasted approximately two to three thousand miles and I have the same problem eml limp mode and on reading the the code with my Autel reader P0238 circuit A high
appears. This always seems to happen when I have been driving two or three miles from cold and under load uphill. When this happens I stop and delete the code and all is ok maybe for 3 or 4 hundred miles.
Any suggestions on how I can fix this problem? I don’t really want to throw money at Fiat dealers because I have no confidence in them from past experience.
Advice please.
Regards.Dave Tring.

Hi, did you fix this?
Cheers
J

 

[theoneandonly]

I checked that when buying it, and thats when it said there was a recall.
Since having it done at the Fiat Commercial place in Truro there have been no more outstanding recalls showing

Are you still having problems. I have sent a Pm the little envelope on rhs on Forum ribbon .
Have you got Multiecuscan yet? Holidays have an anoying habit of getting in the way and then you forget.

 

[jansla]

Hi my problem is with turbo boost sensor on a later engine model, 2015 onwards (x290)
But if I come across a solution I will post it on here , it could be the same simple fix you never know. Have you added a new second earth strap from the engine or gearbox to the chassis? This can fix a lot of stupid problems.
Dave Tring.

Hi Dave! have you managed to get it fixed? I have the same problem and error message with limp mode after 5km from cold start despite having replaced the solenoid valve, MAP-sensor, MAF-sensor and several Fiat-Proffesional workshop visits and the same problem persists.

 

[theoneandonly]

Hi Dave! have you managed to get it fixed? I have the same problem and error message with limp mode after 5km from cold start despite having replaced the solenoid valve, MAP-sensor, MAF-sensor and sev treral Fiat-Proffesional workshop visits and the same problem persists.

Hi i would also be interested in @Dave Tring progress. But back to your problem
What engine and year
What error codes.
Have you got a copy of Multiecuscan?

I have had a search for your posts and it appears you are missing a reply from me since 2023 so sorry for that. I will reply in the main thread.

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

@Dexron there's not much point in opening up the LP EGR to remove just the visible mesh. I've just cut the infeed pipe of my removed 'nearly blocked' cooler to look at using the pipe. Then I looked inside the canister. There is a complex interior with lots of tightly packed fins. All full of...

www.fiatforum.com

 

[jansla]

@theoneandonly my story (and car details) begun 2023, could be found here: https://www.fiatforum.com/threads/error-code-p0236-0238.501453/post-4700665 and later discussed in this multipage thread https://www.fiatforum.com/threads/d...nged-what-do-i-check-next.491167/post-4701623 and you have kindly analysed some of my Multiecuscan data
Last year, november, Fiat-doubtfully-"Proffesional" changed MAF sensor on my van explaining that it is for sure where the problem was. But it was NOT. P0236 and 238 came back under exactly same circumstances the first day I started the van after the winter. In my case there have been and still are only two codes P0236 and 238 but not the 401 thus not sure if it is really the same problem as discussed in Fredastaire's thread. Last summer I've done 6k km without any limp modes until autumn when all was back again. Any way I will update main thread as well