Failing spark plugs can cause the engine to run rough and misfire, which can trigger the Check Engine Light. Continuing to drive under these conditions can damage the catalytic converter. To prevent ignition misfires and Check Engine Light problems, we recommend using only high-quality spark plugs, and preferably spark plugs from the OEM. Spark plugs have different ratings and it's important that the correct ones are used. Spark plug terminals wear down over time and can lead to engine misfires. At minimum, they need to be replaced at the mileage specified by the vehicle manufacturer.