Duke, no one discredits your credentials. All the science in the world, all the math in the world and all the degrees obtainable will not explain why theory and reality simply do not align at times. Point in case, what is your theory on electron flow? Has anyone been able to prove or disprove either of the two most popular theories? From time to time experience can and will contradict theory, it is the education process. My numerous experiences need to respectfully disagree with your educated conclusion that “high engine temperature” has little to do with elevated NoX readings.

I have resolved 15 to 20 cases of high NoX on MB vehicles, the vehicles were tested extensively and we found little if any of the traditional contributing factor as a cause. The majority of the vehicles I was involved with were not fitted with EGR systems (1981 to 1985 380’s and 500’s) with the exception of the following vehicle. I worked on a 450SL that did have an EGR system and it was fully functional according to all MB literature, however the NoX was hovering around 2000. After 15 plus hours devoted to all theories regarding NoX production and ensuring that all systems were operating according to the manufacturer specifications, we needed to shift our attention. That particular vehicle was running around 100c so we installed a new thermostat and rodded out the radiator. After this repair was performed the NoX dropped below 500. Theory vs. experience, theory did not win in that experience.

We can both have our opinions and both opinions can be respected right? Just like electrons flowing from negative to positive,………………when I see the electrons with my two eyes moving from negative to positive than I will believe the theory!