Odd diagnosis.....O2 Sensor???

[xxvengxx]

ok, I put the proper NGK double plat. plugs in my car today but the car had teh same problem, so I ran though the ECU tests again, no codes found. Stated the car, no light (still not sure what this means) I know it's measuring if the exhaust is too rich or too lean. I got it up to 2,000 rpm for 2 minutes, nothing

Slowed the engine, switched to right side, light came on. I reved the engine to 2k again, the light flashed telling me it was right, once I let off the gas, the light stayed on

switched back to the left side and as I reved the engine the light would come on, stay on for a bit, then shut off for a bit, then come back on and so on and so on.

When I idled the motor again the light turned off.

I'm at the point where I think I'm just going to get a new O2 sensor and see if that fixes the problem. I just wanted to get others opinions before I did anything

thanks again