Any ideas on how to diagnose and repair a 97 ford Club Wagon with a V-10 that failed the smog check. Everything else was ok except the HC's were 3X higher then the 150 higheset rate acceptable at idle and at other times. I have the shop manual. I was going to buy the OBD 2 thing but they say it won't do anything unless the check engine light is on. The check engine ligh is not on. any ideas?
Thanks Uriah