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Is Your Check Engine Light On? Consider these Common CEL Culprits.

Last updated 6 years ago

The “check engine” light is part of your vehicle’s onboard diagnostics system, a series of computers which monitor vehicle performance and regulate such variables as engine speed, fuel mixture, and ignition timing. When the onboard diagnostics system finds a problem that it cannot correct, the computer turns on the “check engine” light (CEL). While the easiest way to diagnose a CEL is to visit your local auto repair specialist, here is a list of the most common culprits:

Faulty Spark Plugs
Spark plugs ignite the mixture of fuel and air in your engine to create the combustion that powers your car. If your vehicle’s spark plug cables or wires are even slightly worn out, they will misfire and cause the CEL to turn on. Fortunately, spark plugs are some of the easiest engine components to replace—your local auto repair shop can complete the job in virtually no time at all.

Faulty Oxygen Sensor
The oxygen sensor inside your vehicle’s engine is responsible for measuring the amount of oxygen in the exhaust and for adding or reducing the amount of fuel being delivered to the combustion chambers. In addition to triggering the CEL, a bad O2 sensor may also cause you to get bad gas mileage. To ensure that you aren’t wasting money at the pump, visit your local auto repair shop to have your vehicle’s O2 sensor tested.

Dirty Gas Recirculation Valve
Your vehicle’s exhaust gas recirculation valve (EGR) is designed to reduce exhaust emissions by recirculating gases into the engine’s intake stream. If the EGR gets clogged with oil or dirt, or if it starts to deteriorate, the CEL will turn on. If you notice a strong smell of gas every time you start your vehicle, it may be a sign that the EGR is dirty.

If you’re vehicles “check engine” light is on, then stop by your local Greulich’s Automotive Service & Collision location. We guarantee quality repairs on all automotive services we perform and promise you’ll experience superior customer service each and every time you visit. To find the Greulich’s location nearest you, contact us online or give us a call at (480) 389-2359 today.




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