DPF issues after adblue delete

[dan1w]

Hi guys,

I had a 'reductant pressure too low' fault with the adblue system that was diagnosed as a faulty pump. Specialist wanted 1k to change the pump which given the age and mileage of the car wasn't feasible, I would have tried to fit a used one and get it coded myself but had no time and needed transport so went with an adblue software delete from the specialist. The car is a 2015 A4 2.0 TDI Ultra.

Confirmed with their tech before work was carried out that it wouldn't interfere with DPF regens as a DPF 'below efficiency' fault had come up after the adblue fault and I'd assumed this was as it wasn't regening while the adblue fault was present.

Day after I got the car back the DPF 'check owners manual' warning came up. The vast majority of my driving is motorway anyway but I drove about 60 miles keeping the revs above 2k. No joy so I then drove about 40 miles in 4th gear the day after. No joy with that either and the flashing coil and engine light came on.

I've got an OBDeleven and tried to force a regen both standing and driving and had no luck. The measured soot value was about 30 when I first checked it and was 48 last night. I figured the car might be blocking the regen because the soot value is now so high so I zeroed it and tried again and still no luck, after 40 miles the 'check owners manual' is back. If I monitor measured soot whilst driving I can literally see it ticking up about 3g in 30 miles.

I'm wishing now I'd not got the delete and it seems like it's blocking the regeneration. I'm going to call the specialist today and see what he says.

Any ideas here would be much appreciated. Has anyone had any issues with DPF regens after an adblue delete? Anyone know a way I can check for certain whether the delete is blocking the regens? 

The only force regen instructions for OBDeleven I can find seem a bit outdated so maybe there's a new procedure for the latest app version?

I imagine with the punishment I've now given the DPF it's going to have to come out, how involved is that on the 2.0l TDI Ultra?

Cheers guys,

Dan

 

[Stevey Y]

10 hours ago, dan1w said:

Hi guys,

I had a 'reductant pressure too low' fault with the adblue system that was diagnosed as a faulty pump. Specialist wanted 1k to change the pump which given the age and mileage of the car wasn't feasible, I would have tried to fit a used one and get it coded myself but had no time and needed transport so went with an adblue software delete from the specialist. The car is a 2015 A4 2.0 TDI Ultra.

Confirmed with their tech before work was carried out that it wouldn't interfere with DPF regens as a DPF 'below efficiency' fault had come up after the adblue fault and I'd assumed this was as it wasn't regening while the adblue fault was present.

Day after I got the car back the DPF 'check owners manual' warning came up. The vast majority of my driving is motorway anyway but I drove about 60 miles keeping the revs above 2k. No joy so I then drove about 40 miles in 4th gear the day after. No joy with that either and the flashing coil and engine light came on.

I've got an OBDeleven and tried to force a regen both standing and driving and had no luck. The measured soot value was about 30 when I first checked it and was 48 last night. I figured the car might be blocking the regen because the soot value is now so high so I zeroed it and tried again and still no luck, after 40 miles the 'check owners manual' is back. If I monitor measured soot whilst driving I can literally see it ticking up about 3g in 30 miles.

I'm wishing now I'd not got the delete and it seems like it's blocking the regeneration. I'm going to call the specialist today and see what he says.

Any ideas here would be much appreciated. Has anyone had any issues with DPF regens after an adblue delete? Anyone know a way I can check for certain whether the delete is blocking the regens? 

The only force regen instructions for OBDeleven I can find seem a bit outdated so maybe there's a new procedure for the latest app version?

I imagine with the punishment I've now given the DPF it's going to have to come out, how involved is that on the 2.0l TDI Ultra?

Cheers guys,

Dan

 

Hi I don't think it has anything to do with the delete, you mentioned high milage therefore I would say its probably the EGR cooler inside the DPF that throws up the p2002 fault as the eco thinks the DPF is blocked when it isn't, only just got on to this fault through dialogue with another member Jdragon in the A5 B9 part of the forum have a read it will be an education as yours is virtually the same engine emissions set up.

Steve 

[jdragon]

Interesting read. What is the fault code?

Out of interest; what were you sold as the benefits of the AdBlue delete? And the consequences on the rest of the system?

Steve is right, the EGR cooler is likely at fault here. Your soot values are a little higher than mine, but the limit is 80g for the A5.

Don't keep trying to force the regens, because you risk cracking your DPF.

Before you worry too much, I'd attempt a G450 sensor adaption and monitor for a few weeks.

Not forgetting the Cataclean treatment!

[keithbarneta4]

Sorry to post here guys, I'm new to the forum and have dpf and egr issues with my 2014 a4 2,0 tdi tecknik.

up to now always serviced with main dealer.I was about to part ex but had the orange engine fault light come on. I booked an  an Audi main dealer diagnostic stated a DPF filter fault and the EGR would need replacing (quoted £1950 !!).  This is the 3rd EGR I would have replaced and my cars only done 20k since last change 3 years ago!.

My question. I need to replace OS engine mount under the Extended Warranty (free to me) whilst doing this could mechanic access the EGR more easily, as I could ask for a reduction as the majority of the EGR work is labour?

 

Failing this I'm screwed if I have to pay nearly 2k to replace teh EGR only to part ex my 2015 a4.

 

Otherwise any lower cost option considered

Thanks in advance.

Edited February 17, 2023 by keithbarneta4
add further question

[Stevey Y]

1 hour ago, keithbarneta4 said:

Sorry to post here guys, I'm new to the forum and have dpf and egr issues with my 2014 a4 2,0 tdi tecknik.

up to now always serviced with main dealer.I was about to part ex but had the orange engine fault light come on. I booked an  an Audi main dealer diagnostic stated a DPF filter fault and the EGR would need replacing (quoted £1950 !!).  This is the 3rd EGR I would have replaced and my cars only done 20k since last change 3 years ago!.

My question. I need to replace OS engine mount under the Extended Warranty (free to me) whilst doing this could mechanic access the EGR more easily, as I could ask for a reduction as the majority of the EGR work is labour?

 

Failing this I'm screwed if I have to pay nearly 2k to replace teh EGR only to part ex my 2015 a4.

 

Otherwise any lower cost option considered

Thanks in advance.

Hi the engine mount would have to be removed anyway to gain access to the EGR, BUT without codes we are fishing in the dark, I suspect the low pressure EGR cooler which is sited in the DPF chamber and is very difficult to change, if you look on this post at dragons posting history he had the same problem and got his done at a VAG specialist near him for about a grand, go to a good independent garage and get them to scan the car then come back and post the codes.

Steve.

[keithbarneta4]

 

Thanks Steve

I'll see if I can get the codes from the Audi dealer who diagnosed the fault.

Correction, i have the 2015 facelift A4

 

 

[dan1w]

I am the OP of the resurrected message. If it’s any help to you I used Archoil and it rectified my EGR fault, still no recurrence. 
 

Also, if it’s any help to anyone that stumbles upon this thread later, it was the adblue delete that stopped my regens which got resolved with a software mod.
 

However, it also killed my stop/start which I could not rectify, so if anyone has had an adblue delete on 2.0tdi ultra Audi A4 and managed to maintain their stop/start please let me know where you got it!