Operation CHARM: Car repair manuals for everyone.

P0401

DTC P0401: Insufficient Flow Detected in EGR system

1. Reset the ECM.
2. Start the engine. Hold the engine at 3,000 rpm with no load (in neutral) until the radiator fan comes on. Test-drive under the following conditions.
- Without any electrical load.
- Decelerate from 55 mph (88 km/h) for at least 5 seconds.

3. Check the Temporary DTC with the scan tool.

Is Temporary DTC P0401 indicated?

YES - Clean the intake manifold EGR port with carburetor cleaner. Clean the passage inside the EGR valve with carburetor cleaner or replace the EGR valve.

NO - Intermittent failure, go to step 4.

4. Turn the ignition switch OFF.
5. Disconnect the EGR valve 6P connector.




6. Connect the battery positive terminal to EGR valve connector terminal No.4 with a jumper wire.
7. Start the engine and let it idle, then connect the battery negative terminal No.6 with a jumper wire.

Did the engine stall or run rough?

YES - Intermittent failure, system is OK at this time.

NO - Clean the intake manifold EGR port with carbretor cleaner. Clean the passage inside the EGR valve with carburetor cleaner or replace the EGR valve.