[turbo4]

Not a long time ago our X3 engine light came on. We took the car to the dealer who run the diagnostic and here is a report;

STARTED VEHICLE AND VERIFIED THAT THE CHECK ENGINE LIGHT IS
ON IN VEHICLE. CONNECTED BATTERY CHARGER AND SCANNED
VEHICLE. FAULTS STORED FOR SCR NOX SENSORS AND FUEL
MONITORING SENSORS. ENTERED TEST PLAN FOR AIR MASS SYSTEM
TESTING. AS PER TEST PLAN CHECKED FUNCTION OF THE OXYGEN
SENSORS. NOT CURRENTLY AT TEMP. PREFORMED CHECK OF AIR
FILTERS AND CHARGE PIPES WITH DUCTING ALL ARE CORRECT
PREFORMED 15 MINUTES RUNNING CHECK. FAILED TESTING. TESTING
FAULTS THE PRE CATALYTIC CONVERTER OXYGEN SENSOR.

NEXT PREFORMED SCR SYSTEM TESTING. PREFORMED 50 MINUTE SCR
FUNCTION CEHCK. CHECK FAILED TEST PLAN WANTS BOTH NOX
SENSORS REPLACED BEFORE FURTHER DAIG.

DC 1170-D0000000-12-001 PRE CAT OXYGEN SENSOR
DC 1170-D0000000-10-013 NOX SENSORS.

-----
Dealer wanted us to pay and replace 2 NOX sensors because the computer is telling tech to do it. Its cost $3000.00 CDN.

I am thinking at this point who is "smarter" computer or the tech? In reminds me of people using internet and when a computer ask you to download a file you do it without thinking. This is a BMW way? Do what the computer tells you. When I asked the service rep about it, she told me that this is how BMW does things. Why would I ever go there again?

Took the car to my trusted mechanic who after diagnoses said that only one NOX sensor is faulty.
He decided to take out both NOX sensors and do a good cleaning. Lots of carbon buildup.
He then performed proper regeneration cycle and it completed. We drive mostly short distances in the city so the regen cycle could never complete. So far we had a car for 2 weeks and no issues. Drives much better. It currently at 45km.

My point here is that BMW dealer never explained to me why it happens, tech is only following the computer diagnosis and they wanted 3k to replace both NOX sensors to further continue diag. Well, that did not go well with me. Previously I wanted them to do an oil change and I was quoted over 300.00. When I asked why so much, it was explained to me that because it was diesel. What a bunch of xxx.

One question to owners with BMW diesels, do you guys use Liquid Moly Diesel Particulate Filter DPF Protector as part of your maintenance?

[RickG]

Originally Posted by turbo4

Not a long time ago our X3 engine light came on. We took the car to the dealer who run the diagnostic and here is a report;

STARTED VEHICLE AND VERIFIED THAT THE CHECK ENGINE LIGHT IS
ON IN VEHICLE. CONNECTED BATTERY CHARGER AND SCANNED
VEHICLE. FAULTS STORED FOR SCR NOX SENSORS AND FUEL
MONITORING SENSORS. ENTERED TEST PLAN FOR AIR MASS SYSTEM
TESTING. AS PER TEST PLAN CHECKED FUNCTION OF THE OXYGEN
SENSORS. NOT CURRENTLY AT TEMP. PREFORMED CHECK OF AIR
FILTERS AND CHARGE PIPES WITH DUCTING ALL ARE CORRECT
PREFORMED 15 MINUTES RUNNING CHECK. FAILED TESTING. TESTING
FAULTS THE PRE CATALYTIC CONVERTER OXYGEN SENSOR.

NEXT PREFORMED SCR SYSTEM TESTING. PREFORMED 50 MINUTE SCR
FUNCTION CEHCK. CHECK FAILED TEST PLAN WANTS BOTH NOX
SENSORS REPLACED BEFORE FURTHER DAIG.

DC 1170-D0000000-12-001 PRE CAT OXYGEN SENSOR
DC 1170-D0000000-10-013 NOX SENSORS.

-----
Dealer wanted us to pay and replace 2 NOX sensors because the computer is telling tech to do it. Its cost $3000.00 CDN.

I am thinking at this point who is "smarter" computer or the tech? In reminds me of people using internet and when a computer ask you to download a file you do it without thinking. This is a BMW way? Do what the computer tells you. When I asked the service rep about it, she told me that this is how BMW does things. Why would I ever go there again?

Took the car to my trusted mechanic who after diagnoses said that only one NOX sensor is faulty.
He decided to take out both NOX sensors and do a good cleaning. Lots of carbon buildup.
He then performed proper regeneration cycle and it completed. We drive mostly short distances in the city so the regen cycle could never complete. So far we had a car for 2 weeks and no issues. Drives much better. It currently at 45km.

My point here is that BMW dealer never explained to me why it happens, tech is only following the computer diagnosis and they wanted 3k to replace both NOX sensors to further continue diag. Well, that did not go well with me. Previously I wanted them to do an oil change and I was quoted over 300.00. When I asked why so much, it was explained to me that because it was diesel. What a bunch of xxx.

One question to owners with BMW diesels, do you guys use Liquid Moly Diesel Particulate Filter DPF Protector as part of your maintenance?

What year is your bmw? I have a 2015 and my nox sensor was replaced under warranty last year.... couple months later I had to replace the whole line that goes into the cat with the cat because it was cracked... they told me there was no relation took my 300 bucks or whatever it was just to scan and gave me a big quote lol. I didnt replace it there. When it was dealing with the warranty issue they were spectacular though best treatment I've ever had with a dealership... Unfortunately second time through I didn't deal with the same people

[RickG]

Mine was replaced in ontario, and have less than 100,000km pretty sure warranty is up to 150k

[turbo4]

Unfortunatly these Nox sensors are not covered by the warranty. I also have extended warranty and it does not cover it. Only BMW makes these sensors so you cannot shop/get after market part. Price is 1k per sensor. BMW design of the SCR/DPF system for North America is really bad - 6 different sensors. When the DPF re-generate cycle executes or if it does not the owner has no idea that this is failing. No warning lights. Every year during the warranty you got to the dealer for oil changes. Do they check last regen cycle? At this point they could force it and prevent total failure of the DPF or sensors in the futiure. But, they do not. They just wait until it fails and then ask the owner to pay a lot to get it fixed, and by that I mean they dont even try cleaning it just replacing the expensive parts.
Owner of diesels in NA are never told about that and how this system works befor you buy the car. It is not fully explained in the owners manual.

Many opt at this point to remove/delete the whole system since it is a big problem.

[andreigbs]

OP, you may want to peruse the diesel subforums here (https://f30.bimmerpost.com/forums/fo...play.php?f=488), which several very knowledgeable folks frequent and provide helpful input for a variety of issues specific to diesels.

As for your question on fuel additive: I know BMW discourages their use but I have used them in all other diesels I've had for many hundreds of thousands of miles, without issue. I know firsthand accounts of folks who used LM's DPF Protector to clean their DPF which had triggered the check engine light and regens could not be performed otherwise.

I would say if you don't have it already, get the BimmerLink app and appropriate OBD dongle and you can force regens whenever you wish, along with much better diagnostics and other functions without ever seeing a stealership again.

If you tend to do mostly short trips, be sure to get the car out on the freeway periodically and do a good Italian tune up. I mean run the snot out of it at high rpms, full boost. It will help prevent buildup from occurring as fast. Diesels don't like to be babied.

[RickG]

Originally Posted by turbo4

Unfortunatly these Nox sensors are not covered by the warranty. I also have extended warranty and it does not cover it. Only BMW makes these sensors so you cannot shop/get after market part. Price is 1k per sensor. BMW design of the SCR/DPF system for North America is really bad - 6 different sensors. When the DPF re-generate cycle executes or if it does not the owner has no idea that this is failing. No warning lights. Every year during the warranty you got to the dealer for oil changes. Do they check last regen cycle? At this point they could force it and prevent total failure of the DPF or sensors in the futiure. But, they do not. They just wait until it fails and then ask the owner to pay a lot to get it fixed, and by that I mean they dont even try cleaning it just replacing the expensive parts.
Owner of diesels in NA are never told about that and how this system works befor you buy the car. It is not fully explained in the owners manual.

Many opt at this point to remove/delete the whole system since it is a big problem.

NOx Sensor should have a 10 year warranty in Canada.

from another BMW forum :
"In other news, BMW have just extended the warranty for NOX sensors to 10 years, I am currently trying to get an answer from the dealership on how to get this refunded. They are allegedly looking into that."

I found in the states it's 10 years 120,000miles
Here in Canada I forget what it was can't find that source but think it may have been 150,000km like I said I had mine replaced last year. So if you're under 150,000km I would "def" reach out to them again or try another dealership. This also ties into the emissions warranty here in Canada.

[kevink1]

Luckily while I was waiting on the repair earlier this year I googled and found it was covered by warranty. Was quoted over $700 for the repair. Unfortunately I either had 2 fail, or they replaced the wrong one since a week later I had to go back to have it fixed. And missed 3 days of work since the wrong one was shipped from Dallas, then took 2 days for the replacement. no errors since then, and I went on a 3500 mile road trip.

[turbo4]

Originally Posted by RickG

NOx Sensor should have a 10 year warranty in Canada.

from another BMW forum :
"In other news, BMW have just extended the warranty for NOX sensors to 10 years, I am currently trying to get an answer from the dealership on how to get this refunded. They are allegedly looking into that."

I found in the states it's 10 years 120,000miles
Here in Canada I forget what it was can't find that source but think it may have been 150,000km like I said I had mine replaced last year. So if you're under 150,000km I would "def" reach out to them again or try another dealership. This also ties into the emissions warranty here in Canada.

I found that only pre 2016 diesels are covered by the BMW warranty.
See this link https://static.nhtsa.gov/odi/tsbs/20...53683-9999.pdf

I have 2016 X3 diesel and BMW stopped covering NoX sensors for this car.