P0401 MAZDA Exhaust Gas Recirculation Flow Insufficient Detected

Possible causes – EGR passage clogged– Faulty EGR Vacuum Modulator Valve– Faulty EGR Valve– Faulty EGR solenoid valve– EGR solenoid valve harness is open or shorted– EGR solenoid valve circuit poor electrical connection– Dead (Weak) battery– Faulty EGR temperature sensor and circuit– Exhaust gas leaks Tech description EGR flow malfunction could be caused by a…