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What does the Check Engine Warning Light Mean?

check engine light

You’re driving along and your Check Engine light illuminates the dash. Just what you need as you’re headed to work or an appointment. You may wonder if you should pull over or find a mechanic right away. Whether the light is burning steady or flashing will impact your decision.

What the Check Engine Light does

The Check Engine Light, also referred to as Service Engine Soon or Check Powertrain, is hooked up to the computer diagnostics system in the vehicle. It monitors everything about the powertrain that impacts the emissions system. Each issue is tied to a code, so when the warning light is lit, it can mean many different things.

Common issues indicated by the Check Engine Light

The first thing to check is the gas cap if your model has one. You may have forgotten to tighten it properly the last time you filled up at a station. When the cap is loose, it sends a message to the system of a leak in the vapor recovery system, part of the vehicle’s emissions.

Other common problems which trigger the Check Engine Light includes sensors and spark plug wires. A more serious issue occurs when there is damage to the catalytic converter. In this case, the light may flash rather than burn steadily. The flashing light indicates a more serious problem that should be dealt with right away. The vehicle may be misfiring, which will also lead to a flashing light because it can damage the catalytic converter.

If the Check Engine light is on, you need to have it serviced by a technician who will read the code that goes with the problem. If the light is flashing, don’t continue driving it. Get to your destination and make an appointment to have your Check Engine Light inspected right away before the issue causes serious and expensive damage.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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