Does it have to be on to leave a code for a possible reason for very bad mpg? Usually 16 in city, 15 with AC on, now down to 13 with AC on. New plugs, clean air filter, correct tire pressure, all things done as suggested in this group. Just about 40K on it. I'm taking it in for PA state inspections and I asked them to see if there's a code in the computer for the bad mpg. They said that if the Check Engine light didn't come on, there will be no code. True??
- posted
17 years ago