Recurring NOX sensor issue on 16 model C200 Coupe (petrol)

[Julieoscar]

The garage where my C200 2014 petrol is serviced is saying that my driving style, Miss Daisy, car in comfort setting, auto, never driven hard is not helping the nox issue. They suggest on occasion put into sport mode use the steering wheel paddles when engine hot and get to 4000 revs before changing gear. I’ve never been a boy racer type. Garage offered to take on run for me. They are saying car on occasion needs to be driven hard. Not sure if this explains people repeated faults. Mark.

Ive reported on here several times about my heap of trouble E220 , ive had nox sensors replaced so many times , Ive now got the ad blue fault every 4 to 5 months . I have smoke coming out the exhaust if I drive around town too often so have to rev it up and down the motorway once a week , Your advice about the temperture, sport mode and not buying diesel from the supermarket is a help .

 

[JBell]

It's possible othe makes have same issues, however I don't own them. No other car I ever buy will have any of this crxp on them.

They all have the same problems, most use the same systems

 

[JBell]

Your advice about the temperture, sport mode and not buying diesel from the supermarket is a help .

The problems with short journeys in Diesels is they never get up to temp so they can't clean themselves out. Modern Diesels with AdBlue etc are no use for anyone doing short journeys or under 15k a year with plenty of time to get the car up to temp for a decent period of time.

Diesel is Diesel no matter where you get it from, the only thing to do is put some system cleaner through it every few months

 

[Wighty]

Ive reported on here several times about my heap of trouble E220 , ive had nox sensors replaced so many times , Ive now got the ad blue fault every 4 to 5 months . I have smoke coming out the exhaust if I drive around town too often so have to rev it up and down the motorway once a week , Your advice about the temperture, sport mode and not buying diesel from the supermarket is a help .

You could try the adblue anti crystal additive for the repeated adblue faults
edit …ignore this you have a petrol

 

[ajlsl600]

Tried that. Q no effect

 

[rf065]

You could try the adblue anti crystal additive for the repeated adblue faults
edit …ignore this you have a petrol

Did not help me either.

Only thing that solved my problems was the adblue delete, could not be happier, the car now runs like brand new.

 

[malcolm E53 AMG]

The problems with short journeys in Diesels is they never get up to temp so they can't clean themselves out. Modern Diesels with AdBlue etc are no use for anyone doing short journeys or under 15k a year with plenty of time to get the car up to temp for a decent period of time.

Diesel is Diesel no matter where you get it from, the only thing to do is put some system cleaner through it every few months

That is the thing about the OM642 it soon gets up to temperature so within 3 miles from cold (most of the year) it can start a DPF regen that’s why we hear so little regarding this problem with that engine - I never used supermarket diesel in mine

 

[Wighty]

The problems with short journeys in Diesels is they never get up to temp so they can't clean themselves out. Modern Diesels with AdBlue etc are no use for anyone doing short journeys or under 15k a year with plenty of time to get the car up to temp for a decent period of time.

Diesel is Diesel no matter where you get it from, the only thing to do is put some system cleaner through it every few months

I’ve used supermarket diesel for 120k miles , I do add cetane but have never had a fuel related issue .

 

[rf065]

I’ve used supermarket diesel for 120k miles , I do add cetane but have never had a fuel related issue .

If we're talking about older cars, I ran my CLK220CDi for 150,000 miles on supermarket fuel without adding anything at all and never had a fuel issue.
How times have changed in the name of progress or thinking green.

 

[Srdl]

You could try the adblue anti crystal additive for the repeated adblue faults
edit …ignore this you have a petrol

The one you quoted is diesel!

 

[ajlsl600]

I’ve used supermarket diesel for 120k miles , I do add cetane but have never had a fuel related issue .

When time allows I will interview my deleted adblue and see if any blockage seen. I will also contact my Adblue delete guy see if I can have origional set up on dongle to, maybe, put back at later date, shud that become a sensible thing to do.?

 

[JBell]

That is the thing about the OM642 it soon gets up to temperature so within 3 miles from cold (most of the year) it can start a DPF regen that’s why we hear so little regarding this problem with that engine - I never used supermarket diesel in mine

Yes the OM642 is different, had mine 9 years and 70k now, brilliant engine

Most problems are on the 4pot newer "d" models as they have NoX Sensors and AdBlue systems, the NoX sensors are all being replaced FOC by MB now as they are a known fault and they have been superseeded. They HAVE to be replaced in pairs though, if you replace one the other will go within a few weeks and then you have to do both - utterly ridiculous

70k on Supermarket Diesel and no real problems until I did 2 miles a day and the EGR clogged so now SWMBO uses it for her 20mile a day commute

 

[Julieoscar]

This is my first post to these forums, so apologies in advance if this is not the right place to post and if so please feel free to move it to a more suitable forum.

My 16 plate C200 Coupe (petrol) has a recurring NOX sensor problem. The amber engine warning light comes on and during the service the diagnosis points to a NOX sensor issue.

The car is on very low mileage (only about 3900 miles in 2 years).

I bought the car in March 16 brand new from Robinsons Mercedes in Cambridge and it has only been serviced by them.

The problem occurred for the first time in Nov 16, then in Jan, Feb, April, May 17 and now again in Mar 18.

So far Robinsons Mercedes have been unable to provide any clear explanation about the root cause of the problem or how to completely resolve it. In some cases they've even said that they could not find out what the actual issue is and just reset the warning light. The last time they looked at it, in May 17, they said they replaced the NOX sensor, took the electronics apart and reassembled them and they were confident the issue has been fixed - well, only for 10 months!

I am worried about what will happen after the car is out of warranty (next year, in Mar 19), if the issue keeps recurring after then.

My questions:

• Has anyone else had similar problems with NOX sensors on their Mercedes?
• Is it a known problem with Mercedes, is it only seen on specific models?
• Is there a known solution for this problem?
• Could it be related to the usage profile, i.e. low mileage? (that was mentioned as a possible cause by Mercedes service)
• Could the underlying cause be a more serious fault with the car?
• For recurring problems such as this, what happens when the warranty runs out?

Any information and advice would be greatly appreciated.
Thanks!

sorry if Im repeating myself I cant see my previous replies . I bought mine from Cambridge too I had it on finance and had the NOX sensors replaced twice under warranty then once after warranty for £600 . My car is a 2016 E220 bought at 18 months old with 18 000 miles on the clock . During lockdown I hardly drove it got sensor problem again and was told i needed a £6000 new turbo . Paid off the finance and took it to an independent . I now have the AD BLUE light coming up every few months cheaper just to clean out the filter and add new adblue than replace the tank ( if anyone knows how to get rid of this problem please message 07944416488 ) Also have thick smoke coming out of the exhaust if I do too many short journeys so I have to drive up the motorway every week and rev around town like a maniac . I would like to dump it in the river but my son who has just returned here to work needs a car so Im reluctantly paying £1200 to have the headlight changed , its only done 30 000 miles in 8 years as and most of that is the daytime so no headlights required . My husband bought his new volvo at the same time and apart from the sliding seat being a bit stiff now and again , hes had not one problem . When I went to Mercedes Cambridge with the list of problems they told me Id been unlucky !!!

 

[Steve@Avantgarde]

Sounds like the ad blue metering valve is jammed open.

Adblue systems aren't hard to fix if a) you have the correct diagnosis tools b) can check wiring diagrams c) can work a multimeter.

Most adblue faults we are seeing are being caused by the metering valve crystallising, blocking the injector and then either burning out the pump or taking out the heating line. The best way to combat this is a small additive to your tank when you top up the pigs p..s.

On some E classes there is a wiring loom to the pump that's poorly routed and the wires break.

 

[Julieoscar]

Did not help me either.

Only thing that solved my problems was the adblue delete, could not be happier, the car now runs like brand new.

Hi are you able to tell me how to do the adblue delete my number is 07944416488 Im in cambridge area , or if anyone local can point me in the right direction . thanks

 

[rf065]

Hi are you able to tell me how to do the adblue delete my number is 07944416488 Im in cambridge area , or if anyone local can point me in the right direction . thanks

You need to find someone who does remaps and adblue deletes in your area, you need to check all the reviews and do not get any cowboys that don't really know what they're doing. There are good and bad companies out there.