I have a 89 300E in N. Cal. and I just passed my smog test.
HC CO NO
CO2 O2 Max Meas Max Meas Max Meas
15MPH 15.1 0.1 110 83 0.71 0.18 772 456
25MPH 15.1 0.1 85 81 0.59 0.23 711 435

It looks like my HC was pretty close to the limits at 25MPH. Reading what Duke2.6 has to say, my converter may have been too cool with O2 at 0.1. What would it have changed if my O2 was 0.0? Just seems too close to becoming a gross polluter. At least I am good for another two years.

I changed the plugs and ran Ventil Sauber cleaner into the tank.