95 M3 failed emissions HC too high (Shout out to Vic)

[95gizmo]

As an update to the original post. I think the main reason I was battling with emissions was that I did mechanical fan delete on both my Ti and my M3. As part of the kit they recommend changing to a lower temp thermostat ( I think it was 75C ). On OBD-1 cars don't go there! The coolant temp sensor was keeping the engine in warm up mode and making the fuel mixture rich. I changed the thermostat on both cars to normal range and passed the sniffer with flying colors and improved gas mileage. I have done lower temp thermostat on an OBD-2 M3 with no ill effects, the ECU is different and seems less sensitive to coolant temp.