Engine Code reader and FIXER. Plugs into port under your car dash. Every car after 1996 has one. Reads engine fault codes. Identifiy the problem yourself and fix it without relying on a mechanic. Reset codes with the provided software or app. Works on your cell phone. Connects with Bluetooth. Powerful but easy to use, and provides similar functions as engine code readers used by mechanics for a tiny fraction of the price. Also provides real time read out on engine information and functions while driving including Mas Air Flow, Fuel Economy, etc. Knowledge is power...arm yourself with knowledge and save your mechanics fee.