Hello guys spn4364. Again. And again

Low def quality can be a major pain to trouble shoot. To start with there is no sensor for this code it checks when it sprays after a regen and temps are hot. First check the def with a gauge to make sure it is ok and not bad. Second check outlet nox sensor which sounds like it was replaced so it should be good. Next step I check is def doser make sure the hole isn't plugged or showing signs of over dosing. Most of the time this is where I find the issue. If I am having a hard time getting the code to go away I replace the doser and don't even waste time testing it. While it's loose run a pressure test with insite to check for leaks and run a spray test to test amount of fluid. If anything fails replace doser. To test if you fixed it start the regen and wait till temps hit 1000 + and stop it and go road test for 20 to 30 mintues and let it dose def fluid.

 

Pittsburgh power catalyst is good stuff but easy on the pimping

 

Sorry about pushing it so much, I don't do any social media except this forum, I'm a O/O Had the SPN 4364 code spent $1500 on both Nox and a couple more sensors $1500 in labor code kept popping up get it cleared pop up again. Felt Ike I got screwed. Another trucker told me about MM I bought a half gallon ran all day then the code went off and hasn't came back. Just couldn't believe it. Guess I thought I had to tell everyone I could. Might have been a little to excited about it. My bad lol

 

I’m a fan of the max mileage but I’ve been using it since March & I have gotten the sa 0 spn 4364 fmi 18 code twice in the last 30 days. I got my DPF filter cleaned, new outlet Nox sensor 3 weeks ago & the dosed valve was replaced last November, what else could it be?

 

if that’s you’re only code get insite hooked up and run a SCR Test on it, should narrow it down.