Check Engine Light on - NOx Sensor out?
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S350 BT 4MATIC
Check Engine Light on - NOx Sensor out?
Check Engine light came on yesterday, took it into the dealer today - needs a NOX sensor replaced. Should I go for all of them or let them go, one at a time?
Thanks and Regards
Thanks and Regards
Last edited by Nuru; Sep 19, 2014 at 01:19 PM.
Thread Starter
MBWorld Fanatic!
Joined: Jul 2007
Posts: 1,904
Likes: 29
S350 BT 4MATIC
Thread Starter
MBWorld Fanatic!
Joined: Jul 2007
Posts: 1,904
Likes: 29
S350 BT 4MATIC
OK, another N0x sensor bit the dust, and I am going in to get it replaced. It pulled up a 111800 code "The upper limit value of component NOx sensor downstream of the catalytic converter has been exceeded". Yep another one - NOx sensor. So I will verify that it is a different one and how many this car has. I think you are correct that it has 2 or more. I wished they would have replaced both at the same time when the last one went out.
Out Of Control!!
Joined: Jul 2003
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From: North Scottsdale, AZ
'71 Pinto
EPC shows 1 NOx sensor 
covered by Emissions Warranty up to 3 years/50,000 miles (whichever comes first) depending on state vehicle was first sold. In addition, if it is the sensor again MBUSA should cover previous repair for 1 year/unlimited mileage.
covered by Emissions Warranty up to 3 years/50,000 miles (whichever comes first) depending on state vehicle was first sold. In addition, if it is the sensor again MBUSA should cover previous repair for 1 year/unlimited mileage.
Last edited by konigstiger; Jun 29, 2015 at 12:58 PM.
MBWorld Fanatic!
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2 nox sensors
before start swapping sensors have the scr controller updated and "offending" nox sensor re-learned as there is a bug in older code that will result in nox sensor out of bounds false positive
before start swapping sensors have the scr controller updated and "offending" nox sensor re-learned as there is a bug in older code that will result in nox sensor out of bounds false positive
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W214 E300e
The second one is item No. 580, I believe.
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2012 s350 4 matic
I have a 2012 s350 bluetec 4 matic. I think it has 3 nox sensors. I have replaced two. I have never been as disappointed in a car as I am in this one. Now it need a new adblue pump. I can't believe Mercedes would release a car with an emission system this bad. I have owned at least 6 diesel Mercedes. Loved all of them.
Senior Member
Joined: Jul 2010
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From: Chicago
2008 W463 G500, 2003 Terminator Cobra (710RWHP), 2012 S350 Bluetec, 2010 911 C4S, 2007 VRSCDX
I have a 2012 s350 bluetec 4 matic. I think it has 3 nox sensors. I have replaced two. I have never been as disappointed in a car as I am in this one. Now it need a new adblue pump. I can't believe Mercedes would release a car with an emission system this bad. I have owned at least 6 diesel Mercedes. Loved all of them.
Senior Member
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Posts: 388
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From: Chicago
2008 W463 G500, 2003 Terminator Cobra (710RWHP), 2012 S350 Bluetec, 2010 911 C4S, 2007 VRSCDX
Great!!! I am in Illinois and am looking for someone as well and my system hasnt failed yet. However, most of items are disabled digitally so the cars computer nolonger is looking for the sensors and a response. I am not 100% to all the details of the process. I know of at least one person in NY who can do it, but would prefer to have someone in Illinois would make it much easier.
Senior Member
Joined: Jul 2010
Posts: 388
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From: Chicago
2008 W463 G500, 2003 Terminator Cobra (710RWHP), 2012 S350 Bluetec, 2010 911 C4S, 2007 VRSCDX
So due to the removal of these systems mpg goes up 2-3 per gallon (min) and there will be a bump in power. Makes perfect sense, as now the car can breathe easier.
I am still interested in local options but there isn't much, I am looking tho
Last edited by W109 W211 6.2L; Mar 1, 2018 at 06:12 PM.
Junior Member
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2012 s350 4 matic
Thanks: I really appreciate your sharing this information. I am going to try to contact them tomorrow. Price is okay. I was quoted 950 at dealership to put new ad blue pump in. Then something else will happen. I will keep you informed of progress
Senior Member
Joined: Jul 2010
Posts: 388
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From: Chicago
2008 W463 G500, 2003 Terminator Cobra (710RWHP), 2012 S350 Bluetec, 2010 911 C4S, 2007 VRSCDX
Great keep us posted! I should get my car delivered this week and this will be one of my first modifications made, as the MPG increases allow for it to pay for itself.
Newbie
Joined: Nov 2013
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From: Smyrna, TN
2012 S350
Ad Blu horse ****
I have a 2012 s350 bluetec 4 matic. I think it has 3 nox sensors. I have replaced two. I have never been as disappointed in a car as I am in this one. Now it need a new adblue pump. I can't believe Mercedes would release a car with an emission system this bad. I have owned at least 6 diesel Mercedes. Loved all of them.
Junior Member
Joined: May 2021
Posts: 20
Likes: 4
W166 ML350 BlueTec
OK, another N0x sensor bit the dust, and I am going in to get it replaced. It pulled up a 111800 code "The upper limit value of component NOx sensor downstream of the catalytic converter has been exceeded". Yep another one - NOx sensor. So I will verify that it is a different one and how many this car has. I think you are correct that it has 2 or more. I wished they would have replaced both at the same time when the last one went out.
I have a 2012 ML350 Blutec with the OM642 engine. I have been getting the same 111800 CEL ("The upper limit value of component NOx sensor downstream of the catalytic converter has been exceeded"). I was wondering after you replaced it, did the CEL go away? Its gonna cost me nearly $700 to replace the N0x sensor so I just want to be careful in not throwing away money. Any help will be appreciated. Thanks
