I"m building a off road use only trail rig and was wondering if anybody has ran without oxygen sensors and gutted out the catalytic converter. My converter was getting supper hot, so i cut a hole in it and took the ceramic out. I have a backup converter if this won't work, but thought I'd see what everybody thinks 1st.

 

Off road or not, your upstream O2s are needed for proper engine management. The downstream ones can be fooled with the extensions that are made to get the sensor out of the exhaust stream. The downstream sensors only check to see if the converters are working. I used the ones made by Blox Racing

 

The engine management system (the computer) uses the amount of O2 in the exhaust stream to adjust fuel and combustion metrics to acheive the best stoiciometric levels (best possible oxygen/fuel ratio) for the most efficient operation and power. Removing them is going to make the vehicle run into 'limp mode' and it's going to run like crap.

The catalytic converters are supposed to run 'HOT'......that's why they have a ceramic insert and not one made out of something like cork..

 

thanks for the info, that answers my question.

 

I run without cats. Mine were broken and molten from misfires, so I took them out. I have good upstream O2 sensors, and the vehicle runs fine. I can't say I never get codes, but it runs fine. My Check Engine Light is about as constant as the ABS light, but I know what they actually mean, and if anything changes, I can read any new codes.

Without cats, I believe the only codes you can expect to suffer that are directly related are P0420 and P0430. I just ignore them.