Onboard diagnostics (OBD) systems have been around since the 1980s and were developed to help limit harmful automotive exhaust emissions. Between 1988 and 1995, U.S.-built vehicles came with what's ...

Ignoring a check engine light might feel harmless if the car still runs smoothly, but the warning signals more than a minor inconvenience. Driving with that light on can lead to higher repair costs, ...