Posts Tagged: Insufficient EGR Flow

P0401 code — What it means and how to fix it

Learn what a P0401 code for EGR means and how to fix the problem A P0401 code is defined as Exhaust Gas Recirculation Flow Insufficient Detected; meaning that the commanded amount of EGR flow doesn’t match the actual EGR flow. The EGR system is responsible for diverting a certain amount of exhaust gas to the intake manifold air to reduce combustion chamber temperatures and reduce NOx formation. See this more in-depth post for more information on the EGR system and why it’s needed. The most common causes of a P0401 … Read More