I bought Jardine pipes and loaded the tune from tuneboy for Jars and triple filters. I unchecked the box for the O2 sensor in Tuneboy and unplugged it and have a check engine light.

Questions:
1. Do I need a O2 bypass/delete plug?
2. If the check engine light is on does that mean it is in limp mode?
3. Should I just plug it back in and wrap it up somewhere under or in the bike.
4. If the box for the O2 sensor is unchecked does it still heat?

1. I use the O2 sensor eliminator from Dyno Jet... and don't even bother with the silly TuneBoy box check business.

2. Check engine light is on because you unplugged the O2 sensor without using O2 eliminator (or leaving O2 sensor plugged in with TuneBoy box checked). Your engine is not in limp mode.

3. If you plug the O2 sensor in... it will heat! If wrapped in plastic, it will melt!

4. Yes

If you decide to completely remove the O2 sensor from your pipes, be sure and put a pipe plug in it's place. IMO, a better idea is to use the O2 sensor to feed a real time AF monitor... like WEGO or other.

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Ditto what Hombre said regarding O2 sensor. Also make sure that you click save after checking the box and then click to save the tune, then reload the tune.

Here is how I dealt with the O2 sensor.

How to Install Triple K&Ns Under BearClaw

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