That "Check Engine" light is on nasty son of a gun, and if you are anything like me you have a damn clue about anything under the hood. Before handing over a couple c-notes to a mechanic so he can plug in a fancy computer to figure out what is wrong and fix things that aren't broken—just do it yourself. The CarMD will plug into any vehicle made after 1996 thought the Data Link Connector. Once the CarMD does all of its fancy diagnostic work, you can plug it into your PC to download the diagnostics and maybe figure out what is wrong on your own. Only you can prevent a mechanic from screwing you. $90. – Travis Hudson

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