Octavia 5E 2014 150 BHP TDI Loss of Turbo power (not limp mode)

[Hanifk]

2 days ago the check engine light came on whilst out of town, No on board errors showing. 

The engine was running normally and revving smoothly. 

I had lost the Turbo boost so no real power of the car, it drives well otherwise and is not making any noise from the engine or restricted in anyway/ 

 

Where I am located I dont have a Skoda or VW dealer for a few hundred miles. So I have to be self reliant to finding out the fault. 

My local mechanic is an old timer and does not do diagnostics or work on a computer. 

 

How can I diagnose what the exact fault could be. I feel its a sensor or relay which has stopped the turbo boost going back into the intake.

I do not mind buying a OBDII with VAG tools, but would need some guidance of which unit that can pick up on this fault. As the links I have read dont mention Turbo as a fault they scan for!!

Any help on diag tools is welcome or if anyone has already experienced this and knows the solution, advice welcome..
Thanks in Advance. 

 

[PetrolDave]

You definitely need to do a diagnostics scan, many things can cause the engine to go into limp mode. The preferred tools on here are either OBD11 (go for the Pro version)  or VCDS (make sure you don't get a cheap clone).

 

Where to look? - the engine ECU at address 01.

 

Once you have a fault code scan copy and paste it here.

[Hanifk]

Hi Dave, 

Thanks for the swift reply. 

The car is not in Limp mode. Well not as how others have described their issues. I have no Rev limitation, or loss of power under load. 

I dont have the Turbo power now.. 

I want to diagnose it. But dont know which OBDII device to get.. Have you any suggestions which I can use a reference and make a decision on what I can find here in Italy. 

 

Thanks

 

 

Edited 16 January, 2022 by Hanifk

[PetrolDave]

3 minutes ago, Hanifk said:

I want to diagnose it. But dont know which OBDII device to get.. Have you any suggestions which I can use a reference and make a decision on what I can find here in Italy.

As I said get OBD11 Pro (note that's eleven not II) OBD eleven or VCDS VCDS distributors (scroll down to find a link to the Italian distributor).

[Hanifk]

Hi Dave,   
I managed to get a OBD scan of my car just to find out what the fault could be. 

I received 4 errors:

1.P245300 Particulate Filter Pressure Sensor 'A' Circuit - Range/Performance

2.P245200 Particulate Filter Pressure Sensor 'A' Circuit

3.U112300 Databus Error Value Received

4.U041500 Invalid Data Received From - Anti-Lock Brake System Control Module

 

From the feedback on driving the car I was only aware of the Lack of Turbo boost which would be restricted if there was something awry with the DPF sensor

I can see from the quick search made online the DPF needs to be cleaned, before any sensor is replaced so the new sensor can detect a clear DPF and nor keep going into Regen mode sooner than needed. 

I have not recently seen the Regen mode come on, and have made several long journeys so I am expected it to be clear under normal driving conditions. 

I have to obtain a VCDS unit to be able to code in the new sensor. 

 

Re the ABS error: The last time I had a fault on a sensor it effected my steering system, limited power and I received many other errors on the dash. All caused by the ABS sensor cable being dislodged by a snow chain - reconnecting it back removed all the errors and car has been running normally for 3 years. .

This time I don't get any other messages or symptoms which I did before. 

Only discovered it with the scan. 

 

If anyone has experience with these symptoms or can guide me with the right steps I can take in getting it resolved, I greatly appreciate it 

 

Thanks in Advance. 

Hanif

 

 

 

 

[aki78]

Check your sensor:

 

[Hanifk]

I checked my sensor which is surrounded by a heat shielding faux fabric cover. 

The inside of this cover was full of soot, so I imagine there is a leak somewhere and possible cause of the error. 

Unless this is a normal situation? 

My part number is 03L 906 051B

Which is the 2 pipe version sensor but only the left one has a pipe connected to it!

Is there an alternative part number or single pipe version I can use if it needs replacing? 

I want to check for leakages first to ensure there are no other issues before getting a replacement sensor, unless the soot around it is 'normal' 

The outside local temperature reaches just above freezing at peak during the day so its too cold to spend long time under the bonnet. 

Can only do a few things at a time.. 

 

 

 

 

 

 

 

[J.R.]

Only one pipe is connected, the other is for the baseline atmospheric pressure reading.

 

From what you have recounted:

 

DPF sensor fault

 

Soot escaping from the pipe seal

 

Not heard any regenerations recently.............

 

I would say that the DPF is clogged, the sensor has detected that, stopped any regens from occuring and brought up the MIL indicator light, putting the engine into LOS (limited operating strategy) mode.

 

You have continued driving so the back pressure has overcome the pipe seal to the DPF sensor as witnessed by the soot, this may also have caused the sensor to fail but hopefully it will just be the connections.

 

You are right to start with a DPF clean (an off vehicle one by a specialist not a tin of snake oil) followed by adaption/coding by VCDS to tell the ECU that a new DPF has been fitted also adaption of the existing sensor if its working or the new one to calibrate it to the ambient pressure, its called DPF offset value.

 

 

[aki78]

Not 100% sure that it’s a clogged DPF. Mine was about 75% full when my sensor melted. Yes, the DPF needed cleaning but only 60k kms later.

Maybe the sensor has an invisible hole or crack where the soot can escape. In my case it was only a failed sensor.

Edited 25 January, 2022 by aki78

[Hanifk]

5 minutes ago, J.R. said:

Only one pipe is connected, the other is for the baseline atmospheric pressure reading.

 

From what you have recounted:

 

DPF sensor fault

 

Soot escaping from the pipe seal

 

Not heard any regenerations recently.............

 

I would say that the DPF is clogged, the sensor has detected that, stopped any regens from occuring and brought up the MIL indicator light, putting the engine into LOS (limited operating strategy) mode.

 

You have continued driving so the back pressure has overcome the pipe seal to the DPF sensor as witnessed by the soot, this may also have caused the sensor to fail but hopefully it will just be the connections.

 

You are right to start with a DPF clean (an off vehicle one by a specialist not a tin of snake oil) followed by adaption/coding by VCDS to tell the ECU that a new DPF has been fitted also adaption of the existing sensor if its working or the new one to calibrate it to the ambient pressure, its called DPF offset value.

 

 

Thanks JR. 

 

I have not heard any Regens lately as most of the Kms I have done have been a few short country roads and majority Highway 130 kmh to 150 Kmh speeds, so I don't feel that this is a specific issue in my case. 

 

 

[aki78]

6 minutes ago, Hanifk said:

Thanks JR. 

 

I have not heard any Regens lately as most of the Kms I have done have been a few short country roads and majority Highway 130 kmh to 150 Kmh speeds, so I don't feel that this is a specific issue in my case. 

 

 

Don’t drive your car until you get it fixed.

You’ll need a garage with diagnostic tools anyway. The new sensor needs calibrating and it also worth checking the DPF (soot) level. One of my stupid colleague kept driving his car with this problem and after a few 100 kms the whole engine bay was full of soot, the heat shield was partially burnt, etc. Not a good idea!

[Hanifk]

3 minutes ago, aki78 said:

Don’t drive your car until you get it fixed.

You’ll need a garage with diagnostic tools anyway. The new sensor needs calibrating and it also worth checking the DPF (soot) level. One of my stupid colleague kept driving his car with this problem and after a few 100 kms the whole engine bay was full of soot, the heat shield was partially burnt, etc. Not a good idea!

I should have mentioned it was the driving conditions before the light came on. 

Currently it is off the road and not driven.. 

Getting a garage with VAG diagnostic tools is not going to be easy for me here. I am in a very remote area and very few facilities in my region which cover VAG cars. 

So I  am hoping to gather all the issues and possibilities before I take the necessary steps.. I will need to buy a VCDS system for coding and just ordered a Carista OBDII device to help in the future needs which help to identify issues. 

 

 

[Hanifk]

On 25/01/2022 at 17:55, J.R. said:

Only one pipe is connected, the other is for the baseline atmospheric pressure reading.

 

From what you have recounted:

 

DPF sensor fault

 

Soot escaping from the pipe seal

 

Not heard any regenerations recently.............

 

I would say that the DPF is clogged, the sensor has detected that, stopped any regens from occuring and brought up the MIL indicator light, putting the engine into LOS (limited operating strategy) mode.

 

You have continued driving so the back pressure has overcome the pipe seal to the DPF sensor as witnessed by the soot, this may also have caused the sensor to fail but hopefully it will just be the connections.

 

You are right to start with a DPF clean (an off vehicle one by a specialist not a tin of snake oil) followed by adaption/coding by VCDS to tell the ECU that a new DPF has been fitted also adaption of the existing sensor if its working or the new one to calibrate it to the ambient pressure, its called DPF offset value.

 

 

 

After reading all the suggestions offered and possible causes of the issue, which is a check engine light not a DPF message from the car.  Error code from OBD read. 

1.P245300 Particulate Filter Pressure Sensor 'A' Circuit - Range/Performance

2.P245200 Particulate Filter Pressure Sensor 'A' Circuit

I can summarise the driving situation of the car since I have owned it. 

Bought at 98,000 Kms.. Currently 170,000 Kms in 4 years use. 

Short periods in my local roads with speeds of 60Km/h  Most other times for grocery shopping there are longer stretches on similar roads for 25 Kms and then onto faster A roads and Highway for 50-60 Kms.. 

All other journeys start with the 25Kms local roads and then straight onto highway with speeds low average 130Km/h . Majority of the Kms added to the car are Highway miles. 

In 4 years the DPF cleaning light has come on 3 times.  As much of the driving is at a good speed and long journeys this should have kept the DPF clearer under these driving conditions. 

1 Week before the light appeared and loss of the turbo boost, I had driven on a 900km highway journey. 

 

These are most common causes mentioned on many sites:

 

Defective DPF pressure sensor

Clogged DPF pressure sensor tubes/hoses

Open or shorted circuit/s in the DPF pressure sensor A circuit

Inefficient DPF regeneration

Inoperative active DPF regeneration system

 

The last 2 options seem less relevant due to the driving conditions involved. 

 

So to investigate the 1st 3 plus a possible leak in the tubes measuring the pressures from the DPF due to the amount of soot around the sensor. 

 

if I have missed any other elements to consider I will aim to get some replacement tubing and set about the investigation. 

 

Thanks

Hanif

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[J.R.]

You seem to have a good grasp and understanding of the subject and the issues on your car which is the most important thing, you are also keeping an open mind, not discounting things but concentrating on those you can action and rule out.

 

I think that you will get to the bottom of it fairly quckly the soot will probably lead you to where the leak is have a good listen to the leak at idle and higher revs before making a repair, you can usually hear when the exhaust is obstructed, the leaks make a similar noise to where you might block the tailpipe with  a rag to test for exhaust leaks in the old days.

 

Hopefully it is a leak and not a blocked DPF.

 

Good luck!

[Hanifk]

Today I plugged in a Carista OBD device with the Pro software. 

Lots of errors which were there many were AC and other due to the engine not running. Just reset them and they are gone.. 

However Aside from the DPF error code already mentioned above. 

 

I am unable to find the following new code which is a VAG code 05253. Under Engine section.. 

Searched in many places and not able to locate this 

 

Is there a database of VAG codes which can be searched? 

 

Thanks

Hanif

 

[Hanifk]

DFP sensor update. 

The plastic tube which is connecting the pipe was broken at the sensor end 
Could not be seen until the sensor was removed for inspection. 

Already ordered a replacement. 

 

Does the new sensor need to be coded in before it can work? 

Can the car be driven without causing any damage before the coding is completed? 

 

Any suggestions would be great as having a lot of trouble getting a VCDS system here in Italy 

 

 

 

 

[J.R.]

It will work but really needs the offset value setting, this is calibration of the sensor to atmospheric pressure, the danger is that your old sensor may have been calibrated with a significant offset that the new one does not need or vice versa.

[Hanifk]

Update on the issue:

Wednesday:

The replacement sensor arrived and was the correct one. 

After replacing it and ensuring no other leak points  were there. 
The Fault code was reset. 

A quick drive confirmed that the  power was back and the boost effect of the turbo was back. 

Thursday:

Needed to go to another town 50 Kms away, multi road route with periods of 60Kms speed, Highways of 130Kms and Other roads with 90Kms. 

What I noticed was an even higher increase in Boost and Torque at all speeds and especially over 1,500 rpm. 

The same experience on the return journey. 

 

What I can surmise from this experience is:

1. The leak had been long standing and only when it lost full pressure the issue came to my attention, thus a reduction of boost based on the sensor readings of the DPF. 

2. The new sensor needs re-calibrating and could be reading older values with the new sensor which is causing the increase performance I felt. 

 

As I am not able at present to access a VCDS system to reset the sensor I have to just watch and see for a period and adjust my driving style according to the increased performance.. 

I am not displeased with the extra power. 

But just to be cautious in case readings from the sensor are wrong and calibration will settle it back.

 

Thanks for everyones input and help each suggestion has been helpful in working out the fault and ability to concentrate on a resolution without the more dedicated tools a garage would have to diagnose quicker. 

 

This forum is invaluable for support to  us all . So thank you all on this platform for sharing your knowledge and experiences.

 

Hanif