[cm335d]

Gents, I could use your help on this one.

Yesterday I got my 2011 335d back from Bob Smith BMW, I had brought it in because the SCR Urea Tank had defective heater and level switches. They replaced the SCR tank, three clamps, and filled it with urea. I picked up the car and the service engine soon light was finally gone....well, it was...until this morning on my commute in to work.
With this car, I've learned to just keep my code reader in the back set. Sad to say, but all of us 335d owners know its true. I pulled the following codes:
1. P20EE
2. P0425

Can any of you help advise what these codes are? Are they related to the NOX sensor warranty that BMW extended as well? Thanks in advance for the help.

[dixy2k]

I hope all the work was done under the extended warranty.
If it's true, then let them deal with it. bastards. They never learn anything from their customers. They probably messed something up.

A defective catalyst temperature sensor
A fault or poor connection in the catalyst temperature sensor circuit
A damaged or defective catalyst temperature sensor wiring harness
A faulty oxygen sensor


P20EE
cat related.

When was the last time you had your CBU cleaned up? How many miles on your car?

Might be CBU, but still take it back to the dealer.

[cm335d]

Originally Posted by dixy2k

I hope all the work was done under the extended warranty.
If it's true, then let them deal with it. bastards. They never learn anything from their customers. They probably messed something up.

A defective catalyst temperature sensor
A fault or poor connection in the catalyst temperature sensor circuit
A damaged or defective catalyst temperature sensor wiring harness
A faulty oxygen sensor


P20EE
cat related.

When was the last time you had your CBU cleaned up? How many miles on your car?

Might be CBU, but still take it back to the dealer.

Thanks for the reply! Funny thing happened, I checked the codes again after I drove a few more miles and had cycled the key twice and the P0425 code is gone. Weird.
P20EE is still there though.

I have never cleaned the CBU completely. I only cleaned the intake manifold when I replaced the glow plug controller and 2 glow plugs about 2 years ago at 75k miles. I didn't know you were supposed to clean the head side and didn't look at that time. (doh!) . Now that I know, I have assembled the tooling to walnut blast the ports and then send the intake manifold out for hot tank clean as well, just have been dragging my feet because I know it's a full weekend project. Car now has 102k on it. Runs great and still gets 31.9mpg on average with 50% highway (at 80mph) and 50% city driving.
If you think that 20EE code might be as a result of the CBU, then I'll cancel my appointment to take the car back in to the stealer until I've performed that service. I don't want them trying to charge me the $189 'diagnostic' fee because it wasn't the BMW covered part.

[dixy2k]

I can recommend you a very good shop in Arcadia if that is somewhat close to you.

[cm335d]

Originally Posted by dixy2k

I can recommend you a very good shop in Arcadia if that is somewhat close to you.

That's not too far from me, about an hour drive.

[dixy2k]

He has worked a few diesels before, mine included, and he has his own 335D.

John at EMW
86 West Live Oak Ave
Arcadia, CA 91007
626-445-6600

[cm335d]

Originally Posted by dixy2k

He has worked a few diesels before, mine included, and he has his own 335D.

John at EMW
86 West Live Oak Ave
Arcadia, CA 91007
626-445-6600

Thank you for the info, it is much appreciated!

[dixy2k]

No problem.

[cm335d]

Thought to clean the SCR Urea injector this weekend, since its an easy thing to do. Well, it was caked with a whole bunch of carbon (not urea crystals as I was expecting to see) on the injector itself and also on the hole in the exhaust. After using a small screwdriver and wire brush to clean all of this crap off, I reinstalled it into the car and cleared the codes. Viola! Codes are gone (at least for now and I have cycled the car at least a dozen key cycles).
https://drive.google.com/open?id=1uV...EQxgaKsiW0HkCl

[cm335d]

Update: Same Code (P20EE) Code came on after about 250 miles. Going to try removing the #1 NOX sensor after the turbo to see what it looks like and then #2 after the DPF. I'm suspicious that the Liqui-moly intake cleaner caked these sensors up with carbon goop like it did my EGT Sensor #3 and SCR Urea injector. At least the car still runs fine. Stupid SES light...ugh. Once its paid off next year, I'm deleting all of this crap.

[robnitro]

There's a10yr 120k mile extended warranty on the nox sensors. Unfortunately dealer has to do it

[cm335d]

Originally Posted by robnitro

There's a10yr 120k mile extended warranty on the nox sensors. Unfortunately dealer has to do it

Yes, and if I can ever figure out that my P20EE code is somehow linked to the NOX sensors, I'll be asking a dealer to replace under warranty. I won't be using Bob Smith though, they had their chance to take care of me and failed miserably.