This has me puzzled. I had an exhaust leak with no CEL. Today I replaced the gaskets with the reflex ones and the leak is gone. I reconnected everything I took off and double checked I did. Now, when the car is idling, it's still fine. Then I drive it, and after 1-2 minutes of driving, the cel comes on. I can shut the car off and restart it and the light is off But then comes right back on after about driving 1-2 minutes again. Car runs perfect and runs strong. No drive ability issues. I did disconnect the o2 sensors to drop the X pipe but I reconnected them back up. Tried checking codes using the jumper wire with both engine off and engine running. Didn't get any codes at all. Not sure where to go from here. Want to get some input before I go any further.