Hello, my 92 MTX just failed emissions on High HC..Readings of 2.58 with a limit of 2.5. from what I can read, HC's are highest when its at low speed, up to 30mph, then it levels off to where it should be. I just replaced the front bank O2 sensor, new plugs, airfilter, and oil change on it. Any help from the SHO gods would be awsome. Thanks Erik