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Q: Insufficient EGR flow code

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I am getting a P0401 code - insufficient EGR flow.

The EGR (Exhaust Gas Recirculation) valve is an emissions component that helps most vehicles run cleaner. The valve opens, allowing the exhaust gasses into the intake manifold to dilute the air/fuel mixture, and reduce NOx emissions. The computer monitors values concerning intake air, fuel, and exhaust readings, and captures the EGR fault this way. A malfunctioning EGR valve, or control valve, is common as carbon build-up blocks the the ports that connect the valve to the intake manifold. In the event of a faulty EGR valve or control valve, some time should be taken to inspect and clean any build-up left in the ports. Have a mechanic inspect your vehicle’s emissions system, and perform any necessary repairs. Consider one of our expert team members here at YourMechanic.

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