Nox sensor fault

[Michael79]

Morning,
Some help and advice would be much appreciated. I bought a Mercedes GLC 2017 3 months ago. The engine light came on yesterday so took it to my local garage this morning. They’ve diagnosed the fault as a faulty nox sensor which needs replacing. I’m waiting on the quote back and hoping the cost will be covered by the warranty (only just within the 3 month warranty I was given!) The garage said that this was an Ad Blue / exhaust issue. And that you are better off driving for longer distances? Really? So you can only have a GLC if you drive long distances? Also, when we do get the sensor replaced, will this be a recurring issue? I’m slightly worried now. Thanks for reading

 

[Blobcat]

Hello and welcome,

Unfortunately your issue isn't uncommon... the emissions carp (badly) bolted on to all (not just Mercedes) Diseasal engines do not like short journies and the ad-blue, DPF & Nox sensors all can fail and cause issues. It "should" be fixed under warranty however some owners are getting ££££ bills and others manage to get them covered.
I'm not anti-diesel, I've had loads and loved they way they drove, I wouldn't have a Euro-6 Diesel now unless someone else was picking up the bills

 

[onefortheroad]

Has it had the emissions update done at mb . ??

 

[Michael79]

Hi blobcat,
Thank you for your response. Very helpful. That’s very frustrating and I wish I had done my homework before purchasing. I got the car for my wife who only does short journeys really. It sounds like I may have to think about changing her car. Although it’s such a lovely drive. I just can’t be dealing with these issues month on month as it sounds like a very common issue the more I read. It’s 2021. Drivers shouldn’t be worrying about the length of journey they are doing to keep their car healthy. This is a design fault. Not just with Mercedes admittedly but with the whole diesel / adblue emissions system by the sounds of it. I may write to Mercedes to see what their stance on this is

 

[Michael79]

Has it had the emissions update done at mb . ??

Hi. One for the road. Do you know what? I don’t know. Is there a way to find that out at all?

 

[Blobcat]

Hi. One for the road. Do you know what? I don’t know. Is there a way to find that out at all?

Yes... your EML will come on and the Nox senors will need changing...

(That is unfortunately not a joke)

 

[onefortheroad]

Hi. One for the road. Do you know what? I don’t know. Is there a way to find that out at all?

Put your reg into the mercedes recall website . Google it.

If it hasn't been done yet , I'd advise you let mb fit a new nox and have the software flashed at the same time , otherwise you may find your at square 1 very soon.

Or use a very clever indie.

 

[Botus]

tractors engines are for heavy transport, where high torque is required over a long period.... its why they go in ships or tanks invading countries
sounds like your wife needs an electric vehicle or a Toyota hybrid

 

[mattkh]

tractors engines are for heavy transport, where high torque is required over a long period.... its why they go in ships or tanks invading countries
sounds like your wife needs an electric vehicle or a Toyota hybrid

Or a Honda civic Hybrid.

 

[Botus]

Oh I drove one of them once.... strange brake pedal feel and the whine ragging it on the autobahn wasn't nice