35d NOx sensor research

[Mackskibum]

Has anyone done any research on the Nox sensors from Continental? In looking around the net, Continental is the supplier. There are multiple users of this type sensor, including GM. All of them start out with 5WK9- and then for the 35d 6699C (5WK9-6699C). We pay north of $600, the GM version is 5WK9-6631C available new for $234.95 as a set on ebay.

What I'm wondering is this: Is it possible that the only difference in the sensors is the connector? Kind of like O2 sensors- universal type if you want to solder/heat shrink or OEM connector for easy install. If they are essentially the same, all we would need is the GM connector and pigtail to adapt to the BMW harness.

Does anyone have thoughts?

[Ricky Bobby]

Its actually entirely 100% possible that it is the exact same sensor including connector - Trust me I've seen Lexus part #'s go for 3x the price of Toyota part #'s and they are the same part from the same supplier.

If it had a different connector it should have a separate part number so if you cross referenced part #'s and they match, and the supplier matches, it should be the same part.

This would be super excellent of you to find this out!

[seattle]

I have looked at this a little bit. And yes, it has been suggested by lpcapital here

If you need the part, BMW of Bridgewater still sells older releases of the sensors for $220.
This part number works for both rear and front sensor (they are same essentially, one with slightly longer cable):13628511666

Upstream NOx sensor in my vehicle threw fault at around 90K miles, I replaced it. Now, downstream is throwing the same code. Just ordered the above sensor while in stock. Hopefully good for another 50K miles form here on.

These sensors are essentially a maintenance item, expected to last about 50K miles. Seems to be so in my case. Both replaced at 49K under warranty. Upstream failed at 90K, downstream failed at 108K. Go figure.

[Mackskibum]

I started thinking about this since I am at 85k now on originals.

[yemff]

I got a generic 8 wire nox sensor off eBay for $70 and spliced it on (pre-cat) to the old connector, been working fine for 1000 miles. Lasted me long enough to pass smog, will update this post if it craps out.

[crystalworks]

Originally Posted by yemff

I got a generic 8 wire nox sensor off eBay for $60 and spliced it on (pre-cat) to the old connector, been working fine for 1000 miles. Lasted me long enough to pass smog, will update this post if it craps out.

We're going to need more info on that. Like a link to the ones your purchased, pictures, ISTA use, etc. I just bought 2 NOX sensors on Ebay for $340 that are touted to be "Genuine" but I am pretty sure they are fakes. Very good fakes mind you, but fakes.

[yemff]

https://www.ebay.com/itm/8-Wires-Nox...-127632-2357-0

I used the connectors in the kit, I did not solder. I spliced the generic probe to an old post cat sensor I had. I had a bank 1 implausibility code, I only replaced one sensor; Reset adaptations with ista.

[ard]

The NOX sensors have to be individually calibrated, hence there is a large ‘component’ on the connector with quite a bit of electronic parts….



Are we thinking the new sensor element will work with the existing electronics?!?

[yemff]

It’s working so far; to clarify I had an old post cat sensor from a few years ago when I had to replace that sensor, so I cut the 8 wires on the old sensor keeping the original bmw connector and chip assembly, and spliced the 8 wires to the new probe. If I could figure out how to get inpa in English or how to read pre and post cat nox readings with Ista I would post them.

[ard]

It would be crazy if indeed you dont really need all the electronics and BMW/Bosch just added all that stuff to make an extra $200 per sensor.

O2 sensors are ‘self calibrating’- the metallurgy and construction is such- along with their validated manufacturing- that every one is calibrated and will work with a direct input to the DME.

I dont know why the NOX has the active componentry- my suspicion is that every one is a bit different and needs to be individually calibrated.

Otherwise if any old sensor works and that electronics isnt unique to an individual sensor, Bosch and BMW would simply have moved that ‘smarts’ into the DME. I think.


Also, I do wonder what was going on with BMW extending the NOX sensors warranty and replacing a *TON* of them under warranty. And at the drop of a hat when PUMA troubleshooting….


Interesting.