Yeah, maslaxed ang automotive laws sa Philippines for better or for worse. Catalytic Converters and O2 sensors are not required and were not standard when I purchased my vehicle, kaya it didnt come with any of the two, At the same time, it would be cheaper for the company to assemble the car without these two installed.

However, it does have an onboard computer and fuel injection... I dont know if it would be economical for mitsubishi to manufacture a different kind of computer just for the markets without O2 sensor such as the Philippine market. It might be more economical for them to just ship the same computer for all countries and not to connect an O2 sensor to keep prices down. Kaya I think that if the 1997 Lancer in other countries came with an O2 sensor, then mine might just have the slot for it.