When I did my H22 swap into my 96 hatch, I hooked up all the emission control sensors and devices for the engine. I did not want to have any check engine light hassles AT ALL! They are such a pain in the ass I just did not want to deal with it. If the sensor hookup is there I would definately reccomend using it. By hooking up all the extras I have had NO problems at all with Check Engine lights.....IT HAS BEEN GREAT !!