You may not know a catalytic converter from a carburetor, but you don't need to with the carMD handheld tester. This $90 gizmo connects to your car -- 1996 model or later -- through the universal 16-pin Data Link Connector. You turn on the ignition and it glows green (all systems go) or yellow or red (potential trouble). If you get one of the latter two colors, pop the tester into your PC and go to the CarMD Web site, which will read the data, diagnose the problem and tell you the cause and fix. It will also give you an idea of the repair costs based on national estimates. It's like having your own mechanic.
[Via Gearlog]
