What is hard for me to understand is the principal of garbage in garbage out. From my understanding, California has some very high quality, high cetane, clean burning diesel fuel available at the pumps.
Then, you have the veggie oil people running their vintage OM617 diesel engines on veggie oil......the car travels along smelling like french fries! Then there is biodiesel; there used to be a biodiesel producer in north carolina that created a manufacturing process to produce biodiesel that did not require lye.

It sure appears that diesel emissions/soot levels depends a lot on the fuel the diesel engine is burning.


I really like the OM617 and the OM606 diesel engines.....