DTC P0400: EGR Function: Procedure
- Check exhaust system for leaks. Start engine and warm to operating temperature. Raise and support vehicle so drive wheels are off the ground. Set engine speed between 2000-4000 RPM with transmission in "1" position. Disconnect vacuum hose to EGR valve. See Fig 1. If vacuum exists, check EGR valve for proper operation. See SYSTEM/COMPONENT TESTS
article. If vacuum does not exist, inspect and repair vacuum hose for clogging, cracks or improper connection. If hoses are okay, go to next step.
- Turn ignition off and wait for at least 5 seconds. Start engine and accelerate to 2000 RPM with transmission in "1" position. While disconnecting and reconnecting EGR valve solenoid harness connector, listen for clicking sound of solenoid operating. If solenoid is okay, go to next step. If solenoid is not okay, replace EGR valve solenoid and retest system.
- Inspect EGRC solenoid valve. See DTC P1400: EGR CONTROL (EGRC) SOLENOID VALVE . If EGRC solenoid valve is okay, inspect EGRC-BPT valve. See DTC P0402: EGR CONTROL BACKPRESSURE TRANSDUCER (EGRC-BPT) VALVE. Replace EGRC-BPT valve as required. If EGRC-BPT valve is okay, inspect EGR temperature sensor. If sensor is okay, disconnect and reconnect harness connectors. Check all circuit connectors for clean, tight fit and repair as necessary.
Courtesy of NISSAN MOTOR CO., U.S.A.