2015 Touareg - Repeated CEL and AdBlue Error after filling AdBlue

[TurboABA]

@theonlysandman
First of all, you need to argue that they need to supply a loaner and\or courtesy shuttle.
There's no point in discussing this further as your warranty is now exhausted.

As far as your "logic", it's all relevant. If you don't do your own wrenching, I'm guessing that the delete hardware (depending of course on how much you're deleting) will run you at least $3k. If you do the whole delete thing (EGR, EGR cooler, DPF, NOx, DEF), you're closer to $8k (or more) by the time someone else does all that.

Personally, if I was YOU, and I just got a new Catalyst and sensor(s) 35k ago, I'd let it go until it broke again as I'd expect another 100k worth of life out of these replaced components.

It all depends on your wallet, how you use\rely on your vehicle, and what your intended ownership plans are, etc.

 

[TurboABA]

Here's an example of how I confirmed that my NOx sensor was dead prior to letting VW fix it under warranty, after being greeted with a MIL.
Log #661718

 

[theonlysandman]

Yup -- they did the free shuttle home. and even discounted rental cars but 7 times in two years is crazy IMO.

So, to be clear you would not replace the Catalytic convert pipe just the sensor and keep driving?
That could also make sense to me especially since the price of the pipe is: $2200.

 

[TurboABA]

I would not replace anything that didn't need replacing.
Since we don't have any data\evidence of what actually failed, we don't know if the CAT needed to be replaced.
It's very feasible, that your sensor failed, and as a result, the CAT stopped regenerating. If we knew how long you drove under those conditions, we could make an educated guess as to the feasibility of that theory.
So, if some wrench monkey just replaced the sensor because that's what the code told him, but didn't perform readiness, etc. then, your CAT would've still been all clogged up, even with the new sensor..... then you'd be greeted with another MIL a few days\weeks after that, you'd take it back and they'd throw a new CAT at it...... know what I mean?

I only replace what needs to be replaced, or what's broken. But if the only tool you have is the CEL\MIL, then you have no idea what's broken.

 

[showdown 42]

This thread sounds so familiar to me. Sorry for your aggravation,I know how you feel. Been there done that.

 

[Capt.Aidan]

Just got the Treg back from a 260k km service. 300km driven, CEL, and adBlue countdown.

Seems that almost every time the adBlue is topped up, it gives me a count down.

Anyone have a similar experience?

 

[TurboABA]

What does VCDS tell you?

 

[Capt.Aidan]

Taking it back to my mechanic tomorrow. I'll get the scan report from them and share here.

 

[TurboABA]

You need your own VCDS if you want to know what's going on. Otherwise you're blind and have to reply on whatever you're being told. First you need to know what's throwing the code, theb you need to dig into specific measuring blocks, sensors, etc.

 

[Capt.Aidan]

You need your own VCDS if you want to know what's going on. Otherwise you're blind and have to reply on whatever you're being told. First you need to know what's throwing the code, theb you need to dig into specific measuring blocks, sensors, etc.

Definitely agree. Will be looking into getting my own soon.

 

[TurboABA]

What exactly is a 260k service anyways?

 

[Capt.Aidan]

What exactly is a 260k service anyways?

Inspection plus
Fuel filter
Cabin filter
Oil change
AdBlue top up
And a couple other things I'm forgetting

 

[TurboABA]

Coincidence that your DEF was just topped up and now you have errors? Or did they just top it up with junk instead of proper fluid?

 

[Capt.Aidan]

100% good DEF my mechanic uses the OEM stuff from the VW to ensure that bad DEF isn't a factor

 

[TurboABA]

Interesting. I've never purchased DEF from the dealer, always done my own top ups, and have never had the death countdown after a fill.... Only while running out while towing. I can't wait to see these codes.

 

[Capt.Aidan]

Interesting. I've never purchased DEF from the dealer, always done my own top ups, and have never had the death countdown after a fill.... Only while running out while towing. I can't wait to see these codes.

I've had it happen with third party DEF, dealership fill up, and at my independent mechanic.

Can almost guarantee the codes will be P204f, P229F, P20EE, and P207F. They are all NOX catalyst/sensor faults.

 

[TurboABA]

Make sure you look at the FF data otherwise the code readout is nearly useless. Unless you like just throwing parts at it (expensive ones too as none of those sensors are cheap)

 

[Capt.Aidan]

Alright so this what came back from my scan this morning. As suspected the four faults that I had previously mentioned. Any thoughts?

6 Faults Found:

31036 - NOx Sensor 2 Bank 1
P22A1 00 [096] - Signal too Large
Intermittent - Not Confirmed - Tested Since Memory Clear

9954 - NOx Reductant Consumption too Low
P20F4 00 [040] - -
Intermittent - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 263223 km
Date: 2023.06.11
Time: 00:28:12

Engine RPM: 1256.50 /min
Normed load value: 0.0 %
Vehicle speed: 36 km/h
Coolant temperature: 88 °C
Intake air temperature: 29 °C
Ambient air pressure: 980 mbar
Voltage terminal 30: 14.280 V
Unlearning counter according OBD: 39
Long-term adaptation of reduction agent dosage: 1.81
Measured NOx conversion range 1: 0.000
Efficiency threshold of NOx conversion range 1: 0.000
Mean temperature of SCR catalyst: 333.6 °C
NOx sensor 1: NOx concentration: 32 ppm
NOx sensor 2: NOx concentration: 121 ppm
Particle filter: unburned fuel calculated: 0.000

9567 - NOx Sensor 2 Bank 1
P229F 00 [096] - Implausible Signal
Intermittent - Not Confirmed - Tested Since Memory Clear

5608 - No Communications with Steering Angle Sender (G85)
U0126 00 [032] - -
Intermittent - Not Confirmed - Tested Since Memory Clear

9953 - Reductant Quality Performance
P207F 00 [237] - -
MIL ON - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 263223 km
Date: 2023.06.11
Time: 00:28:12

Engine RPM: 1251.50 /min
Normed load value: 0.0 %
Vehicle speed: 36 km/h
Coolant temperature: 88 °C
Intake air temperature: 29 °C
Ambient air pressure: 980 mbar
Voltage terminal 30: 14.280 V
Unlearning counter according OBD: 40
Long-term adaptation of reduction agent dosage: 1.81
Measured NOx conversion range 1: 0.000
Efficiency threshold of NOx conversion range 1: 0.000
Mean temperature of SCR catalyst: 333.9 °C
NOx sensor 1: NOx concentration: 32 ppm
NOx sensor 2: NOx concentration: 121 ppm
Particle filter: unburned fuel calculated: 0.000

17277 - SCR NOx Catalyst Bank 1
P20EE 00 [096] - Efficiency too Low
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 263222 km
Date: 2023.06.11
Time: 00:26:38

Engine RPM: 1711.50 /min
Normed load value: 84.3 %
Vehicle speed: 86 km/h
Coolant temperature: 87 °C
Intake air temperature: 29 °C
Ambient air pressure: 980 mbar
Voltage terminal 30: 14.300 V
Unlearning counter according OBD: 38
SCR efficiency test overall: 35.70 %
SCR error threshold of efficiency test: 45.00 %
SCR efficiency test 2: 0.319
SCR efficiency test 1: 0.424
Particle filter: unburned fuel calculated: 0.002
Mean temperature of SCR catalyst: 338.6 °C
Long-term adaptation of reduction agent dosage: 1.71

 

[TurboABA]

Long-term adaptation of reduction agent dosage: 1.81

This is an issue. Normal range is something like 0.90-1.10 if I recall correctly. Your DEF injector is most likely clogged. Rip it out and inspect it.

 

[Capt.Aidan]

Thank you. Will give it a try and see what we come out with.

 

[TurboABA]

So, what did you end up finding?

 

[Capt.Aidan]

So, what did you end up finding?

Since clearing the codes. I've driven 5K kms issue free will see about replacing the injector on the next service.

 

[TurboABA]

Since clearing the codes. I've driven 5K kms issue free will see about replacing the injector on the next service.

Check your dosage adaptation to see that it's dropped back into the acceptable range.

Long-term adaptation of reduction agent dosage: 1.71