I put an O/R H pipe on the stang, and have been driving it without MIL's for about 500 miles. Finally last night the SES light came on. Time for MIL's right? Wrong... this morning, I jump in the car and the light is out. Drove about 50 miles, still no light. What gives, I thought once the light came on, the only way to get rid of it was to reset the codes or the computer?