How to Gap Spark Plugs at Home with a Gap Tool

Learn how to properly check and gap spark plugs at home to factory spec before installing them in your car. In this video, I walk through how to use a standard coin-style spark plug gap gauge tool to measure and adjust the electrode gap correctly. Even "pre-gapped" spark plugs from the factory can shift during shipping or differ from your vehicle's exact specifications—like the 0.044" spec needed for this 2016 Mazda CX-3. Follow along step-by-step so you don't damage the delicate center electrode or bend the ground strap too far. Timestamps: 0:00 - Why you need to gap spark plugs before install 0:06 - How the coin gap gauge tool works 0:28 - Checking the initial factory gap safely 1:08 - How to widen and adjust the gap gently 1:56 - Verifying the final factory spec measurement Tools & Items Used: Coin-style spark plug gap tool / gauge Replacement spark plugs (OEM spec)