Peter Ruttan you may try your chance but you have to understand that this sensor along with all exhaust componants suffers damage from high temperature so not sure it works. Sensor might perhaps also suffer damage from cleaners, soot is really harsh get rid of. Have one to replace so why not give it a try.

Eric CHEUNG sorry for the late reply but I don't think I had to do any special adaptation just erased the fault code but if you put in a used one the make sure that the part number is the same or a compatible number check with a Audi dealer to know how many possible number are interchangeable.

Hi I'm from St Isidore New Brunswick and I check you're fault code P0403 Exhaust gas recirculation EGR N18 I change one before on a Q7 but not sure if it's the same fault do you know what kind of part have been replace to solved this fault. I will check tomorrow if it was the same fault.

hichem87 I can sell you one if they are still available ? I say this because not long ago I wanted to buy a EGT temperature sensor From VW and they did not want to sell me one but the NOX sensor in the video wasn’t bought at Audi . If you’re from Canada or USA then you should check with your local Dealer because it might be under the Emissions extension warranty?

eBay nox for 75$

They both measure the exhaust gases but they don't measure the same gases from the exhaust : NOx sensor, as it's name says, measures nitrogen oxides, while the lambda measures oxygen.

Kobi Suissa no it's not the same but similar the oxygen sensor looks for the quantity of oxygen in the exhaust system and the NOX sensor you guessed it the NOX sensor read the amount of NOX in the exhaust system one big difference is the NOX sensor is much more expensive than a oxygen sensor and it seems it comes with a module attached to it compared to a Oxygen sensor there is only a wire and connector.

If I remember correctly the first one is screwed close to the turbo and the module is bolted on the driver side shocks mount under the hood and the second one if aproximately at the middle of the vehicle the module is bolted under the plastic shield on the passenger side

This is how they come as a replacement it’s hard to know if it’s the NOX sensor that is bad or the metal box and I don’t know if you can buy a replacement sensor alone and then splice the wires to the old box .

@@V10PDTDI thank you For the quick response

Yes the first model to get DEF system was the V6 TDI in the 2009 Touareg in North America the second one was the 2012 Passat TDI with the 2.0 litres common rail engine with air to water intercooler the Q7 and the Touareg shares the same system I haven't seen many problems with the DEF system because when they are new the dealer deals with it now from 2015 and up all VW and Audi will have the DEF system they also have completely new engine including water to air intercooler system.

the way things are going all will be water to air cold air systems

Yes it is more efficient and the intake air travel less distance to be he combustion chamber so less lag and less chance of water condensing in the intercooler like the first gen common rail engine and even plagued the Ford ecoboost v6 engine .

V10PDTDI hahha the eco boost works good when it works but anyone i know with them have alot of issues, thats just the engine to anyways haha