Knox sencer

[skorski]

what makes a check engine light come on with a knox sencer code 'comes on and goes off.2014 3500

 

[smittyd174]

I have a 2016 3500 and it went crazy. Check engine light would come on for a couple days and then go out. It was also trying to do regens and fail and then the light would come on again. Took to the dealer to figure it out and they checked the codes and cleared them. Drove for a couple days and wham here we go again. Back to the shop and because they cleared the old codes they knew exactly what the issue was and its fairly common. The upstream nox sensor gets water in it and basically goes crazy. They blew the water out of it cleared the codes and good to go until the new one came in 2 weeks later. Worked perfect after drying it out and ever since. It is bolted on the frame and the probe goes into exhaust just behind the turbo.

 

[skorski]

Thanks that is what is going on with my 14 each time I go to napa or auto zone and have it checked the light goes out . once it stayed out for a year how do I keep the water out is it coming from the fuel or the rain.

 

[smittyd174]

It's à design flaw and they have supposedly fixed. I will tell you that you have to be sure thats the issue as that sensor will set you back a crap load of cash not sure how much American but they run around $500 -700 Canadian. There is also an upstream and a downstream nox sensor so you really need to know which one. Check You Tube to find there exact locations. Good Luck.

 

[skorski]

Thanks