Code: 1 Oxygen Content

My ECU is flashing a code 1. The engine light comes on for a bit then it goes off again. I was wondering if this means my oxygen sensor is going bad, or it is maybe just not getting enough air. Not sure when last the air filter was changed, so I am going to change that anyways, but was wondering of other reasons for the code 1 if anyone knows of any specific quirks or not. Car is a 1990 Integra GS.

Thanks,

more than likely, your o2 sensor is gone. test it or swap it.