Off engine exhaust smell

[jdjj]

Howdy, I'm in mid-south Texas with 2015 Ram with 160,000 miles and the Temperature dipped to 11degrees F for 2 days and stayed 20 degrees for another 2 days three weeks ago in Texas (occurs once in 25 years). My 2015 ecodiesel had an offensive smell all during this time. I finally pinpointed it to my exhaust. It smelled like turpentine or a burnt electric motor. That is the best smell i could attribute it to. it was strong if you pulled into a garage, and outside with 20 mph winds you could smell it strongly 30 yards away. i have 2 codes showing up PO128 and P20EE. I'm replacing the thermostat (PO128) now and the other is a NOX sensor code which i thought was the problem; not sure. But the smell quit when it got 50 - 70 degrees. Any ideas? 2015 Ram with 160,000 miles

 

[BoostN]

Welcome.. Burnt smell typically comes from the DPF in regen mode or just coming out of it. They put off a strong burnt smell usually. At least mine always have..