DTC P0401: EGR System Insufficient Flow Detected
- Perform PCM reset procedure. See PCM RESET PROCEDURE/CLEARING DIAGNOSTIC TROUBLE CODES
under SELF-DIAGNOSTIC SYSTEM. Connect scan tool. Test drive vehicle with no electrical load. Decelerate from 55 MPH for at least 5 seconds. If DTC P0401 does not reset, problem is intermittent, go to next step. If DTC P0401 resets, clean intake manifold EGR port and EGR passage with carburetor cleaner. Clean passage inside EGR valve with carburetor cleaner, or replace EGR valve.
- Turn ignition switch off. Disconnect EGR valve 6-pin harness connector. Using fused jumper wire, connect positive battery terminal to EGR valve 6-pin connector terminal No. 4. See Fig 1
. See appropriate wiring diagram under ENGINE PERFORMANCE in WIRING DIAGRAMS. Start engine and let idle. Using fused jumper wire connect negative battery terminal to EGR valve 6-pin connector terminal No. 6. If engine stalls or runs rough, problem is intermittent. System is okay at this time. If engine does not stall or run rough, clean intake manifold EGR port and EGR passage with carburetor cleaner. Clean passage inside EGR valve with carburetor cleaner, or replace EGR valve.
Courtesy of AMERICAN HONDA MOTOR CO., INC.