View Full Version : Question Touran fsi NOx sensor

30-09-2009, 08:32 PM
Hi ive got a touran in with codes 17443 p1035 and 17441 p1033 engine BAG relating to NOx sensor problem. there appears to be three sensors two lamda sensors and a pencil shaped sensor in the cat i guessed this one was the NOx sensor, but when i ordered it what came looked like a lamda sensor with a control unit 300 quids worth, can anyone tell me if this the NOx sensor:1zhelp:

30-09-2009, 08:54 PM
What is the part number of the part you have received, 03C 907 807 D?

01-10-2009, 08:50 PM
Hi crasher
yes thats the number they sent me

01-10-2009, 10:03 PM
That is the post cat NOX sensor.

27-03-2010, 03:13 PM
What does the post cat NOx sensor do?
I have the same code come up on my Golf 2.0 FSI BLX.

27-03-2010, 05:30 PM

27-03-2010, 05:49 PM
There is a known issue with these sensors. I can't remember the details off hand, but sensors built before a certain date were to be replaced. Later ones were OK but the software in the engine control unit was to be updated. The build date is on the control box. It's a number something like 30/04. I'll check my notes when I go back to work and post the details.


27-03-2010, 06:28 PM
Thanks,the car seems to run OK,I just got VCDS Lead and I plug it in to my golf to activated it and one fault code came up .Nox sensor

27-03-2011, 08:12 PM
I read in another forum that when changing the NOX sensor (Touran 1.6 FSI 2004 ) a software update is needed. What happen if one only mounts the new sensor without updating the software ?

30-03-2011, 09:30 AM
Is your error permanent?

Do you really need to replace the sensor?

I've had this error twice now on my 2004 Touran 1.6 FSI Both times I just reset the error.

It's just passed it's MOT, emissions are fine.

So if it only flags this error once in a blue moon, I will live with it rather than spend hundreds messing about with new sensors.

01-04-2011, 10:13 PM
Where is the nox sensor located ?


16-07-2011, 07:02 PM
It looks that I have a same problem with this expensive car spare part like a Nox-sensor. I have a Touran 1,6 FSI from 2003 and it has a yellow light on the screen. After deleting fault it`s possible to drive around 2 ~ 3 days and the light is back again.

Today I have checked the system before this yellow light and it was shown a next fault:

1 Fault Found:
17441 - Sensor for NOx (G295): Signal too Low
P1033 - 002 - Lower Limit Exceeded

Like I understood then it`s no other possibilities then to change this sensor to new one?

16-07-2011, 07:52 PM
I mentioned this to my local (non VW) garage.

He says there are usually two sensors, one eich side of the CAT in the exhaust system.

He sold me an expensive tin of petrol additive to clean the sensors. A month later the light came on again, same fault.

I now just reset it every few weeks when it comes on. I'll only get bothered about replacing sensors if it causes the emmissions to fail an MOT.

I do have another problem at the moment, there's an exhaust leak at the front flexi joint, so that's probably not helping.

While I like the car for what it is, little niggles like this are not what I expect from VW. I certainly didn't have any issues like this with the VW golf we had before, that just went on and on and on, with none of this silly diagnostic rubbish to bother you.

16-07-2011, 08:15 PM
Thank`s for fast answer!

Yes, it looks two sensors.

Does it helped this petrol additive to drive a whole month without this light? How it`s possible to know a name of this and would it be possible to buy it from a usual spare parts shop?

Would`nt be this light problem binded with your new problem with exhaust leaking?