Onboard diagnostics tracks hundreds of different vehicle functions, from the oxygen sensors in the exhaust system to the crankshaft position sensor, transmission shift solenoids to ignition coils ...

Instead of an integrated scan tool with a small, monochrome LCD, like the majority of models available, BlueDriver consists of an OBD-II dongle connecting to a smartphone through Bluetooth.

One of the most common reasons your check engine light comes on is a faulty oxygen sensor. Here's how to detect problems with the sensors and how to fix them.