Modern cars generate mountains of diagnostic data, and choosing the right OBD-II scanner can make the difference between guesswork and real fixes.

Once upon a time, you could diagnose the culprit of your Mazda MX-5 Miata's check engine light with a paperclip. We now use OBD-II technology for that.

HP Tuners cracked the engine control module for GM's LT6 and LT7 V-8s, and then a modded ZR1 registered 1180 horsepower at the wheels.

From Maverick to Super Duty to E-Transit, a software bug can kill trailer lights and brakes.