Are the rear O2 sensors a must?

[69chvelle]

So there is no negative effect on horsepower or milage? I've been searching and reading all morning. Someone said they used sparkplug defoulers to pull the O2 sensors out of the exhaust a little and the light went off. I would like to buy a used set of O2 sims or something to fix it temporarily until I can afford a tune. Also, I agree with you that something might go wrong and I won't know since the light is already on. I gotta figure something out soon though.

[tanz45]

Had my LT's on for a few weeks with no problems. Just can't afford a tune right now. If there is a major problem, the engine light will flash rather than be solid. Or just stop by an autozone once a week if there is one and get the scanner put on for free just to check.

[69chvelle]

If there is a major problem, the engine light will flash rather than be solid.

So this is true? Also, I can clear the codes and/or read them with my superchips tuner. They will come back on within a few minutes, but I guess I could at least keep a check on any other codes.