On my gf's car this code appears after about 15 miles. The car starts and runs fine. Air filter is new. The plugs are the correct shade of brown, I've checked the MAF sensor which is perfectly clean ...

Answer:That's a new one for me, and I cannot see it having any effect on preventing a P0420 DTC, but it is illegal. P0420 indicates the catalytic converter has lost its efficiency in reducing harmful ...

Your check engine light can come on a host of reasons, ranging from a loose gas cap to a faulty engine component. If you see a light illuminated on your dashboard, you can use an OBD2 scanner to ...