I have a graymarket E30 that was imported new in 1986. I took it for an emissions test and it failed, which really doesn't surprise me, but the question is "what can I do to make it comply?" The only thing that did not pass was the NO levels which were 3.0+, whereas the limit is 1.0+. The car has no O2 sensors but does have a catalytic converter. It is low mileage and is impeccably maintained. The only thing I can think of is to replace the converter and see if a new one helps.

Anybody got any insight?

(other than overthrow a government who thinks my old Bimmer is the cause of global warming, but Exxon, DuPont and Monsanto need fewer emission regulations)

did you make sure the car was warmed up and didn't sit toolong before going on the dyno?

yes, it was thoroughly warmed