Golf 1.6 FSi 2004 Nox sensor fault

[Golf 1.6FSi 04]

Hi

I've not had my golf long but after the first week of owning it the fault light came on. I've had it diagnosed and the guy has tested everything and it leads to the NOX sensor. I've spoken to VW and they want £492+vat and then two hours labour invluding a software update, a total of over £700! I have been trying to source the part from a breaker or aftermarket but they still seem very expensive. My diagnostic guy said he will then clear the fault but only VW seem to offer the update.

The part no is 03C 907 807 D. I've seen lots with different letters at the end (a,c and f) are these the same sensor?

Has anyone got any other ideas or had the same problem??

[Flash2]

There was a tech bulletin issued by VW about trouble codes relating to the NOX sensors. You had to check the build date marked on the sensor control unit and if it was built before a certain date, it was to be replaced and a software update carried out.

The letter at the end of the part number usually changes when the part has been updated in some way, so if your original is a 'D' you wouldn't want to replace it with anything with an A - C which would be an earlier version. You also wouldn't want to replace it with anything with a build date earlier than what was on the bulletin. Not that that helps you much since you don't have the bulletin. If I come across it, I'll post the details.

Jim.

[Golf 1.6FSi 04]

Thanks for the reply.

I have now fitted a Nox sensor from a breaker. It's a newer part than what was fitted to the car and the car instantly ran better. About three days after I fitted it the light came back on. I'm taking the car into VW for the software update on Saturday, will this help? The only other thing was I could still feel a slight misfire at idle even after the new sensor. Do you think this is related or another issue?

Thanks Adam

[Flash2]

Did you have the car rescanned to see if it's the same trouble code now as before you replaced the sensor?
It's impossible to say if the software update will help if you don't know if it's the same code. As for your idle misfire, I doubt that would be related to the NOX sensor.

Jim.