DTC Troubleshooting

Control System DTCs

DTC Troubleshooting: P0457

DTC P0457 : EVAP System Leak Detected/Fuel Fill Cap Loose or Missing

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information How To Troubleshoot The Fuel And Emissions Systems.

1. Fuel fill cap installation check:

Fuel fill cap installation check
-1. Check the fuel fill cap (the cap must say TIGHTEN TO CLICK). It should turn 1/4 turn after it's tight, then it clicks.

Is the correct fuel fill cap installed and properly tightened?
-YES- Go to step 2.
-NO- Replace the fuel fill cap or tighten the cap, then do the repair verification.

2. Fuel fill cap seal and fuel fill pipe mating surface visual check:

Fuel fill cap seal and fuel fill pipe mating surface visual check
-1. Check the fuel fill cap seal (A) and the fuel fill pipe mating surface (B). Verify that the fuel fill cap tether cord (C) is not caught under the cap.





Is the fuel fill cap seal missing or damaged, is the fuel fill pipe damaged, or is the tether cord caught under the cap?
-YES- Replace the fuel fill cap or the fuel fill pipe, then do the repair verification.
-NO- The fuel fill cap and the fuel fill pipe are OK. Go to step 3.

3. Problem verification:

Problem verification
-1. Turn the ignition switch to ON (II).

-2. Clear the DTC with the HDS.

-3. Do the EVAP FUNCTION TEST with the HDS.

Is the result OK?
-YES- Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the FTP sensor, the EVAP canister vent shut valve, and the ECM.
-NO- The failure is duplicated. Go to step 4.

4. EVAP canister vent shut valve operation check:

EVAP canister vent shut valve operation check
-1. Clear the DTC with the HDS.

-2. Turn the ignition switch to LOCK (0).

-3. Remove the EVAP canister vent shut valve from the EVAP canister Service and Repair.

-4. Connect the 2P connector to the EVAP canister vent shut valve.

-5. Turn the ignition switch to ON (II).

-6. Select EVAP CVS ON in the INSPECTION MENU with the HDS.

-7. Check the EVAP canister vent shut valve (A) operation.





Does the valve operate?
-YES- The EVAP canister vent shut valve is OK. Go to step 5.
-NO- Replace the EVAP canister vent shut valve Service and Repair, then do the repair verification.

5. EVAP canister vent line check:

EVAP canister vent line check
-1. Check the routing of the EVAP canister vent tube.

Is there any damage or blockage?
-YES- Remove the blockage and replace the EVAP canister vent tube if needed, then do the repair verification.
-NO- Do the DTC P0455 troubleshooting DTC Troubleshooting.

Repair verification:

-1. Turn the ignition switch to LOCK (0).

-2. Install the parts in the reverse order of removal.

-3. Turn the ignition switch to ON (II).

-4. Reset the ECM with the HDS How To Troubleshoot The Fuel And Emissions Systems.

-5. Do the ECM idle learn procedure ECM/PCM Idle Learn Procedure.

-6. Do the EVAP FUNCTION TEST with the HDS.

Is the result OK?
-YES- Troubleshooting is complete.
-NO- Check for poor connections or loose terminals at the FTP sensor, the EVAP canister vent shut valve, and the ECM, then go to step 1.