Just bought an O2 sensor for no reason.

[zachattack_5491]

I did the O2 sensor diagnostic. You know where you put the ECU in mode 2 while it's started. The check engine light is supposed to turn on and off at least 5 times in 10 seconds. First sensor failed the test (at least that's what I thought), so I got another one. It is doing the same exact thing. It stays on rich for about 20 seconds, then it might switch to lean for 5. There's no pattern in the way it switches, it's completely random.

The problem I'm having, is my car is surging at all speeds. Not just a little hesitation type surge either, like huge fuel cut type surge. Any ideas? This is SUPPOSED to be my DD.