P0400 mazda. The EGR system is designed to reduce nitrogen oxide emissions by recirculating a portion of the exhaust gases back into the combustion chambers to be re-burned. Learn what Exhaust Gas Recirculation Flow Malfunction means, location and how to repair. It directs a portion of exhaust gases back into the engine intake to lower the combustion temperature, read more how the EGR system work. To Date, I've: Cleaned the intake with the intake manifold on the vehicle. To get a detailed, expedited response from a mechanic, please make a $9. You’ll need a good scan tool to command the EGR solenoid to open or close. Repair Information for P0400 Mazda code. Make: Mazda Code: P0400 Definition: EGR System Flow Malfunction Description: Vehicle driven to a speed of over 7 mph, then back to idle speed, ECT sensor signal more than 131ºF, and the PCM detected little or no change in the EGR Differential Pressure sensor (DPFE) with the EGR vent commanded “on” and then “off” in the EGR Monitor test. We’ll cover what you can do without one first. com OBD2 Code P0400 Mazda definition: The exhaust gas recirculation (EGR) valve is vacuum controlled valve that regulates the amount of exhaust gases that re-enter the cylinders. 6vz6 hnsu wf5dl xd hlxh sig 0rzee pzwrdu idxv 6yz7