You have a 1997 Neon service engine light came on Codes show it's a O2 sensor you replaced it light still comes on says same thing What could be wrong Car is idleing faster now?

Answer 1

Did you properly clear the code from the computer after replacing the O2 sensor? If you haven't cleared the code the computer has no way of knowing if the sensor was replaced or if it's just temporarily reading something. The procedure is different for many vehicles so you may need to look through the owners manual to figure out how to clear the code. The easy way to clear the codes is to disconnect the POSITIVE battery cable for at least 5 minutes. This will clear the codes unless there is a new problem than the code will re-appear. there are (2) o2 sensors 1 upstream - 1 downstream maybe you replaved the wrong one just a thought