Modern vehicles are rolling computers, and diagnosing them is no longer as simple as pulling a basic trouble code. The L ...

️ Editor's note: This product category requires new testing about once a year. We'll update this article with the most recent information when it's available. Modern cars are technological marvels, ...

"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." Modern cars are technological marvels, and understanding what’s happening under the hood has never been ...

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With the advent of smartphones, there are lots of ways to diagnose your car, but none are as easy as an OBD-II diagnostic tool. Nothing lets you dive so deep into all the data your car creates.

Seeing your vehicle's check-engine light come on can throw a wrench in your travel plans. It can also feel a little scary: Does it mean your ride is headed for the scrapyard? Or is there a simple fix?