Problem with the Adblue system

2013 Passat TDI SEL:
Back in December, the check engine light came on and VCDS found fault codes:
P026A - Charge Air Cooler - efficiency below threshold
Intermittent - not confirmed - tested since memory clear

P20EE - SCR NOx Catalyst Bank 1 - efficiency too low
MIL ON - Intermittent - Confirmed - tested since memory clear

I took the car into the dealership. The MIL light was off when I dropped it off. They ran their tests and said the car was fine -- it didn't show a problem when they tested it. The MIL did not return.


Fast forward to yesterday morning on my drive to work. No MIL (per se) but a warning pops up on the display "200 miles until no start" and an amber warning flashes on and off every 5 seconds to warn about the ADblue system. There was no 1500 mile warning about needing to refill the Adblue tank.

By the time I get home, the warning is at "150 miles until no start."
Scanned the car with VCDS and found:

P20EE - SCR NOx Catalyst Bank 1 - efficiency too low
Intermittent - not confirmed - tested since memory clear

P208E - Reductant Injector Valve (Bank 1) - Stuck Closed
Intermittent - not confirmed - tested since memory clear

Additional tidbit of information include the reducing agent fill level is 77%,
so the DEF tank is not low.


I will drop the car off at the dealership for them to look at on Monday morning and see what VW says.

I believe I am very close to the 51,000 mile mark since my "emissions fix" so my fingers are crossed.

Replace the adblue tank and equipment is what is called for IIRC. When you get the 200 mile warning without the 1500 mile warning first it usually means equipment failure. There are some post here about this. Try a search. Should be covered by the warranty if still in effect for you. Keep those fingers crossed!

check under the hood, see if that injector is all crystallized.

740GLE said:

check under the hood, see if that injector is all crystallized.

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I tried to look for that, but I wasn't exactly sure where it is. I looked to the right (passenger side) rear of the motor where I believe the DPF is located. Nothing was readily visible. I was looking down from the top.

ahh you have a 2013, a gen 2, i thought you had a 15, my bad, nothing can be seen under the hood. The Gen 2 injector is under the car, can't easily be seen unless you crawl under it.

When I drove the car to the dealership on Sunday, the flashing warning message was gone. So of course when they looked at it, they could see the code, but didn't find a problem when they ran their tests. They topped off the ad-blue and called it good. No charge.

From the paperwork:
C/S faults in the system P20EE and P208E please check and advise
No MIL when started car...
Found P208E00 reductant injection valve stuck close bank1 unit 1
Ran test plan for N474-reducing agent injection valve.
System working normal at this time... most likely b/c of low ad blue. System working normal again.

So they topped up the tank even though it had shown 77%?

I have a feeling you'll be back to see them again.

The service person I talked to on the phone before I took the car in suggested topping off the tank to make the issue go away. I thought it was a stupid idea, but (they said) they did it anyway. I haven't scanned the car since to double check. They didn't touch the new, unopened container of Peak DEF I had in the trunk.

I've had 2 ad blue related alerts from the car in the past 3 months. Nothing was done to address them. Both times, the error message went away and it tested fine by the time I got the car to the dealer. I'm sure that more issues are coming. It makes me want to look for a more permanent solution to the ad blue issues. (Hypothetically, of course.)

https://malonetuning.com/

just saying.

740GLE said:

https://malonetuning.com/
just saying.

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I had the same problem since the "fix". I went stage 2 Malone with a Rawtek exhaust. If you get the red light of death don't worry, disconnect battery and while keeping terminals from battery jumper between the posative and negative for 30-60 minutes. It gets rid of red light and then you can start car and drive to shop. VW fix does not work and it will cost you to fix after warranty. Tune is the way to go.

Berks Tom, Did this ever get resolved? Mine has almost the exact issue. 200 miles to no restart, add blue tank full.

buffa98 said:

Berks Tom, Did this ever get resolved? Mine has almost the exact issue. 200 miles to no restart, add blue tank full.

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Whatever the issue is with my car has not been resolved/fixed. After getting the original warning -- "xxx miles until no start", I parked the car for a few days until I could get it to the dealer. By the time I started the car to drive it to the dealer, the light and warning had gone away. Best I can say is that the issue is dormant -- most likely lurking around and waiting to pounce on me at a more opportune time.


As stated by some others, the best way to make sure it doesn't come back is with a tune and a new exhaust. However, that is not in my near-term plans.


On a related note, the car has now thrown a 2201 to say it didn't like the measurements from the NOX sensor. A thread from 2015 https://forums.tdiclub.com/showthread.php?t=451913 suggests cleaning the sensor. I will try that before taking the car to the local TDI guru. As I'm now out of warranty, the car will not be going to the dealer.

berks_tom said:

Whatever the issue is with my car has not been resolved/fixed. After getting the original warning -- "xxx miles until no start", I parked the car for a few days until I could get it to the dealer. By the time I started the car to drive it to the dealer, the light and warning had gone away. Best I can say is that the issue is dormant -- most likely lurking around and waiting to pounce on me at a more opportune time.


As stated by some others, the best way to make sure it doesn't come back is with a tune and a new exhaust. However, that is not in my near-term plans.


On a related note, the car has now thrown a 2201 to say it didn't like the measurements from the NOX sensor. A thread from 2015 https://forums.tdiclub.com/showthread.php?t=451913 suggests cleaning the sensor. I will try that before taking the car to the local TDI guru. As I'm now out of warranty, the car will not be going to the dealer.

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Well mine wound up being the ad blue injector, it was only putting in 152 ML of adblue. The range is 155-180ml. It was covered under warranty, but that doesn't help when the dealership service department was closed. I do have to give kudos to Harper VW in Knoxville, one their mechanics was working on his car and agreed to look at it.

As soon as this is out of warranty Malone stage 2 and a rawtech exhaust are being installed.

Any one know how to do the add blue delete?

Den said:

Any one know how to do the add blue delete?

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Yeah buy a dpf delete and a tune. When you swap the exhaust you take out the injector. And a tune turns it off. Just deleted my 12