You hear a new, disturbing noise coming from your engine, open the hood, look around, and find nothing. Now what? Before you reach for a conveniently-placed torque wrench to try the ol’ “love tap,” ...

The top end of the technology ladder is held by a scan tool. This car diagnostic tool plugs into the OBD-II port (“OBD” is an acronym for on-board diagnostics, and the “II” designates the second ...