Why Does a Check Engine Light Blink?

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A blinking check engine light means that the onboard diagnostic system detected a problem with the engine. A blinking light, rather than a steady light, often indicates a serious engine misfire. A driver with a blinking light should head directly to the repair shop.

The check engine light comes on once when the driver starts the car. It should go off within a few seconds. A check engine light that stays on indicates a problem with the car. With a blinking light, the driver should check for signs of engine misfires, such as overheating. It might also mean there is an issue with the catalytic converter, which would need immediate attention.

If the light is steady, the driver should first check the gas cap and gas cap seal to ensure that they are not the problem. If a gas cap or seal was the problem, the light should go off within a few drives. If not, the driver should go to the repair shop for diagnostics. Some possible problems include a misfiring spark plug or corroded cables.

Although a car might seem to function just fine with the engine light on, the light indicates that a problem is present. The longer the driver waits, the more expensive and dangerous the problem can become.