Q: Check Engine light on

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The Check Engine light is coming on.

The powertrain control module (PCM) takes inputs from dozens of sensors. It then uses this information to control outputs such as fuel delivery and emissions equipment. If the PCM detects a problem anywhere in the system it will illuminate the Check Engine Light. There are literally hundreds of potential causes for the light being on. A trained professional will be able to retrieve the corresponding diagnostic trouble codes to analyze your vehicle and make the repairs that will clear the Check Engine Light.

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