x5 35d SES codes - NOx sensor
 

2011 x5 35d with 165,000km

A new Shell station opened in our area and was the first to carry their V-Power diesel. A few weeks back the wife headed out and filled up using the v-power for the first time. She called me before leaving the parking lot because as soon as she started moving, the SES light came on.

My first instinct because of the timing was something fuel related, but when I pulled the codes it was all NOx sensor related. Burned through that tank as quick as possible anyways, cleared all the codes, they all ended up coming back. So the timing could have just been purely coincidental.

Here are the codes I'm pulling from Carly:
00475f - NOx sensor before DeNOx catalytic converter linear lambda or heating stop
00475e - NOx sensore before DeNOx catalytic converter linear lambda or heating stop
004bf5 - Too long invalid NOx sensor upstream of the DeNOx catalyst NOx signal
0046b9 - NOx sensor Nox filtered difference to the calculated NOx measurement signal too low before the DeNOx catalyst plausibility

I don't want to start throwing money at parts before knowing what's wrong. Looking at this I would think the place to start would be the upstream NOx sensor since all codes relate to before cat. Looking at some parts they seem to indicate left bank or right bank, but I've never heard of there being 2?

I'm mechanically inclined, have built many cars from the frame up, but not a diesel expert and there doesn't seem to be much out there on these specific codes. Looking for advise from those smarter than I.

Sounds like you are on the right path. There is no left bank/right bank for the diesel (obviously).

Check out realoem.com for the OEM part number then start checking around.

You can also probably find the sensors used, as many folks are deleting the emissions equipment. (As I did, I sold the sensors for $75 for both)

Well now you've got my attention. I never once thought of deleting the emissions equipment. We don't have any sort of emissions testing here at all.

I'm seeing these sensors brand new are roughly $1,000 CAD. I'm sure that can go a long ways towards an emissions delete.

I spent $1400 USD on all hardware and software to do the deletes.

The exhaust I ordered actually came out of Canada. BuzzKen (Ken Duncan) is the man up there. Depending on where you are, you might be able to have him do the work. I DIY'd the hardware and sent the DDE out to DUDMD Tuning for mine.

Do you know of any other way to have the tuning done other than mailing it out? This is the wife's daily and I can just imagine the hassle she'll give me if I tell her it'll be down for 2-3 weeks.

So, you should be trouble free! However, you can turn the software back on, correct?

Ken can do it all if you are nearby to him. A bit of googling for "Buzzken" should tell you a lot.

Afraid its not that simple. Besides, you are removing the hardware that those parts of the software are looking for.

I've been slowly doing some digging into this to learn as much as I can about the procedure. I've come across a few horror stories about various tuners and fitment issues etc...

I'm wondering if anybody has any experience with the Circuit Werks DPF delete kit?

Compared to the buzzken kit listed above, it's about $670 CDN less expensive. But it appears to only come with the DPF delete pipe and not the pipe for the SCR delete. But looking at the buzzken kit, that SCR pipe looks to be a straight pipe that any exhaust shop could do for less than $100. It is also missing the EGR block off plate which I'm having a hard time finding a source for these plates. Thoughts or suggestions?

Haven’t seen the Circuit works kits, but most of the pipes you find on eBay are for the European models and are not a direct bolt on.

Since I was doing all the work in my yard, bolt-on was key.