[selimthegrim]

Yes, I own a VW TDI, I know the difference between the two. AFAIK, EGR adjusts the combustion temperature so as to avoid an overly NOx-producing lean burn. I was responding to the blanket characterization he made in this statement quoted below.

>Many equally horrible solutions to this problem are employed...Others require a separate tank of catalytic fluid that must be filled regularly. _One thing that all of the designs have in common_ (emphasis mine) is poor performance and piss-poor fuel economy. Many vehicles from multiple manufacturers have had trouble with catching on fire due to emissions control systems.