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Home >> Saturn >> 2000 >> LS2 Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0401: EGR Flow Insufficient >> Circuit Description
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Circuit Description

The Exhaust Gas Recirculation (EGR) valve is used to reduce combustion temperature by introducing non-volatile exhaust gas into combustion chambers. DTC will set if actual manifold pressure is less than 65 percent of calculated pressure (based on engine load and EGR position) and engine speed is between 1600-2200 RPM and altitude at less than 9000 feet.