2016 GMC Canyon, 2.8L Duramax Diesel..."Exhaust Fluid Quality Poor" Fix!!

So, my 2016 GMC Canyon, with the 2.8L Duramax Diesel, recently threw a warning of "Exhaust Fluid Quality Poor" on the dash. This warning will eventually throw the truck into limp mode if not addressed. In this video, I show and explain how I fixed it...with the help of my little brother.
Gear I use to make videos:
-iPhone 12 Pro Max
-DJI Pocket 2
-DJI Osmo Action
-DJI Air 2S
-DaVinci Resolve
-Neewer Tripods

[@dancrawford174]

We had the same issue of poor quality DEF, getting -100 readings on the NOX sensor output. I change both the NOX sensors and ran a regen. Afterwards I saw the NOX readings looking normal, then it started injecting DEF and watched the NOX go down to almost none. I was thinking I was going to have to replace the DEF injector, but got lucky and it was still good. I suspect I'll have to replace it at some point, so I'll have it on hand. The ZR2 runs so much better now! I was using the Launch 431 V+ to diagnose the system.

[@natetran]

Glad to hear u got it figured out Dan!

[@Rover19666]

Nice, inexpensive scanner is the iCar, used it today to fix the exhaust fluid quality issue, no codes, compared contribution of nox 1 and 2 while driving, record and/or watch on phone, nox 2 should run about 10% ish of the contribution of nox 1, replaced Nox1, ran a reductant fluid quality test (like a regen but only at 2k rpm) and good to go.

[@natetran]

Great input, thanks for sharing!

[@juliorego4560]

Good video I got the same problem 😩

[@natetran]

Hope this helped you in some way…good luck with the fix!!

[@waynecorbit8475]

No one should have this engine without also having an I-Dash. You can see easily what is actually going on in real time….decide if you just have a bad batch of DEF…clear the codes and drive it off or actual bad sensors. I could ignore my failed Particulate Sensor for 2 years till the part was cheap and available for $150 By watching DPF soot levels in real time I knew the engine was rutnning fine and poor quality and glitch prone emissions sytem were to blame. Set of sensor tools is good to keep on board.

[@natetran]

Thanks for the input:..maybe I can pick one up with a Black Friday deal somewhere.

[@jimwiskus8862]

Wow 33 mpg, I’m impressed. I get maybe 25-26 mpg with my 2016 2.8L diesel Canyon. It seems to run fine other than my mileage discrepancy. No dash lights. I was curious if your truck has always done that well mileage wise? Thank you for your time.

[@natetran]

I’m at ~157k miles currently. I have not reset my “A-mpg tracker” which is just shy of 27mpg; this of course includes winter driving where I will use 4WD from time to time, and will let the truck run and idle much more. This also includes towing a small trailer and/or our 28’ camper from time to time. When I commute to my current office (~90 mi round trip) it’s mostly highway, and I’m usually just putting along in the slow lane. So it could very well just be that I drive slow. I do like to keep my tire pressures relatively high, usually around 38-40 psi. One other note... I did take my front air dam off….i swear it dropped efficiency slightly, but I have no controlled data to actually prove that.

[@wrcole66]

Just wondering if that cured your issue? I have a 2019 2.8L Duramax and get the "exhaust fluid quality poor" code almost on a daily basis, but it only stays on for a short ride and then is clear... IDK. The dealership looked but if it's not happening when they scan, it won't give a code.

[@natetran]

So far so good…at about 125k mi now, so put on a good number of miles since the fix and no issues or codes. As I stated in the video, we had to do the regen for everything to work properly after swapping in new NOx sensors.

[@codedog007]

If it happens again have them just force the regeneration/DEF system service bay test

[@wrcole66]

After doing more research, I found BlueDef Platinum was my issue all along. The timeline fit for when I started using the Platinum and the code, so switched back to regular BlueDef and now no more exhaust fluid quality poor messages. IDK why but that’s my verdict.

[@cristianaguila5908]

Hi can you help me , is that sensor the one that read the DEF level as well? I have a Colorado 2016 and I need replace the DEF LEVEL SENSOR

[@natetran]

great question....i'm not sure....i'll ask my mechanic brother.

[@htorres8409]

It's a pain in the ass that def I still can't regenerate it after how many regenerations the def light was deactivated. and they change the 2 sensors that you changed

[@jamesa8851]

It has to get to normal exhaust gas temp before it reads nox

[@truthwillsetyoufree1503]

had the same issue and i didnt replace sensor just cleaned them.....computer reset itself.

[@natetran]

Good to know…I’ve cleaned my old ones as “emergency spares”.

[@truthwillsetyoufree1503]

@@natetran good luck to us both

[@rudyshoplopez7366]

I was gonna ask this, if anyone has just cleanned the sensors?! I will try this first! Thanks!! I have my check engine light on code p1478

[@bocockrell1569]

My display came on and gave me the 100 mile warning and went off but so far it hasnt come back up and my truck only has 1600 miles on it. got any ideas?

[@natetran]

if your truck only has 1600 miles on it, since it is under warranty, I would have it checked out by your dealer. that sucks man...but get as much stuff documented under warranty if you can.

[@duckwacker8720]

Delete the turd.

[@saulmoreno3252]

That same message came at 128k

[@natetran]

hope u get it fixed.

[@duckwacker8720]

It should have been fully deleted before you ever had an issue. These are very easily prevented issues. Emissions do not belong on any diesel.

[@natetran]

Agree…if I ever have any other emissions issues, will most likely go down that route. We’ll see how long I have this truck for…at 130k mi now.

[@JoshuaIS1]

@@natetran But how in 2023? I feel like the moron coal smokers ruined it for us.

[@natetran]

@@JoshuaIS1 you’re probably right…I’m at 135k.

[@JoshuaIS1]

I now have this damn issue! Wtf lol @ 189k ​@@natetran

[@natetran]

@@JoshuaIS1good luck with the fix!

[@michaelglenn2106]

I did this and it didn't work

[@codedog007]

Did you run the regeneration procedure with a compatible scantool? Thats basically what you have to do… the nox sensors can get dirty but the regen is the key. Basically the truck has to be warm(heated up)… then with the scan tool you run the test. It idles the truck at various rpms but essentially it cleans the particulate filter in the exhaust system and tests the rest of the DEF system.

[@michaelglenn2106]

@@codedog007 yeah when I took it back to the dealership they said it didn't work because the software on my computers was out of date

[@duncanmacdonald9266]

All the crap is soon to fall off mine... nox sensors, def quality 🙄 I'm done with the error codes. I also have a bit of a shudder in the transmission, I guess the 6 speed isn't much better than the 8 speed. GM needs to get their shit together on torque converter quality or I'll be jumping ship on my next purchase.

[@natetran]

If I have another emissions related issue I might delete…what truck would you buy next?

[@codedog007]

Flush your trans

[@duckwacker8720]

Your first stop after leaving the dealership should have been the delete shop.

[@codedog007]

Just flush the trans… then in 20-30k miles do it again. The torque converter clutch shutter while in lockup is almost always fixed with trans fluid exchange. Its been a ford/chevy issues for years.