DTC P0455: EVAP System Large Leak Detected; DTC P0456: EVAP System Very Small Leak Detected (2017)
Special Tools Required
-Vacuum Pump/Gauge, 0-30 inHg Snap-on YA4000A or equivalent, commercially available
-Vacuum/Pressure Gauge, 0-4 inHg 07JAZ-001000B
NOTICE:
The fuel system is designed to allow specified maximum vacuum and pressure conditions. Do not deviate from the vacuum and pressure tests as indicated in these procedures. Excessive pressure/vacuum would damage the EVAP components or cause eventual fuel tank failure.
NOTE:
- Before you troubleshoot, review the general troubleshooting information - Refer to: How to Troubleshoot the Fuel and Emissions Systems (2017) .
- Fresh fuel has a higher volatility that will create greater pressure/vacuum. The best condition for testing is less than a full tank of fresh fuel. If possible, to assist in leak detection, add 1 gallon of fresh fuel to the tank (as long as it will not fill the tank), just before starting these procedures.
| DTC Description | Confirmed DTC | Pending DTC |
|---|---|---|
| P0455 EVAP System Large Leak Detected | ||
| P0456 EVAP System Very Small Leak Detected |
DTC (PGM-FI)
- Fuel fill cap installation check
-1. Turn the vehicle to the OFF (LOCK) mode.
- 2. 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.
- Fuel fill cap seal and fuel fill pipe mating surface 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.
NO
Go to step 3.
- EVAP canister vent hose check
-1. Check the EVAP canister vent hose (A) for a blockage or a restriction.
Is there a blockage or a restriction in the hose?
YES
Remove a blockage or a restriction, if needed, replace the EVAP canister vent hose.
NO
Go to step 4.
- Fuel tank vapor recirculation tube visual check
-1. Check for a poor connection or damage at the fuel tank vapor recirculation tube.
Is the tube OK?
YES
The tube is OK. Go to step 5.
NO
- EVAP canister purge valve leak check
-1. Remove the intake air duct A/B.
- 2. Disconnect the hose (A) from the 3-way joint (B) in the engine compartment, then connect a T-fitting (C), a vacuum gauge, and a vacuum pump/gauge, 0 - 30 inHg, to the 3-way joint as shown.
- 3. Slowly apply about 2 kPa (0.6 inHg, 15 mmHg) of vacuum to the hose.
Does it hold vacuum for 1 minute?
YES
Go to step 8.
NO
Go to step 6.
- EVAP canister purge valve 1 leak check
-1. Remove the T-fitting, the vacuum gauge, and the vacuum pump/gauge, 0 - 30 inHg, from the 3-way joint, then reconnect the hose.
- 2. Disconnect the hose (A) of EVAP canister purge valve 1 (B) from the intake manifold, then connect the T-fitting (C), the vacuum gauge, and the vacuum pump/gauge, 0 - 30 inHg, to EVAP canister purge valve 1 as shown.
- 3. Slowly apply about 2 kPa (0.6 inHg, 15 mmHg) of vacuum to the hose.
Does it hold vacuum for 1 minute?
YES
Go to step 7.
NO
- EVAP canister purge valve 2 leak check
-1. Remove the T-fitting, the vacuum gauge, and the vacuum pump/gauge, 0 - 30 inHg, from EVAP canister purge valve 1, then reconnect the hose.
- 2. Disconnect the hose (A) of EVAP canister purge valve 2 (B) from the throttle body, then connect the T-fitting (C), the vacuum gauge, and the vacuum pump/gauge, 0 - 30 inHg, to EVAP canister purge valve 2 as shown.
- 3. Slowly apply about 2 kPa (0.6 inHg, 15 mmHg) of vacuum to the hose.
Does it hold vacuum for 1 minute?
YES
Leak is not detected at EVAP canister purge valve 2. Check for a leakage at the 3-way joint and the hoses between the 3-way joint and each EVAP canister purge valve.
NO
- Problem verification
-1. Remove the T-fitting, the vacuum gauge, and the vacuum pump/gauge, 0 - 30 inHg, from the 3-way joint, then reconnect the hose.
- 2. Turn the vehicle to the ON mode.
- 3. Clear the DTC with the HDS.
- 4. Select the EVAP TEST in the INSPECTION MENU, then select the FUNCTION TEST with the HDS.
FUNCTION TEST
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, EVAP canister purge valve 1, EVAP canister purge valve 2, the EVAP canister vent shut valve, and the PCM. If the on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot - Refer to: How to Troubleshoot the Fuel and Emissions Systems (2017) . If the vehicle returns with the same DTC, continue with step 9.
NO
The failure is duplicated. Go to step 9.
- Determine possible failure area (EVAP canister vent shut valve, others)
-1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Disconnect the fuel tank vapor recirculation tube (A) from the EVAP canister (B), and plug the EVAP canister port (C).
- 3. Disconnect the hose (A) from the 3-way joint (B), and connect the vacuum pump/gauge, 0 - 30 inHg, to the hose as shown.
- 4. Turn the vehicle to the ON mode.
- 5. Select the EVAP TEST in the INSPECTION MENU, and do the CVS ON in the SOLENOID TEST with the HDS.
SOLENOID TEST - CVS
Apply vacuum to the hose until the FTP reads 1.90 V (-0.59 inHg, -15.1 mmHg).
NOTE: Be careful not to exceed the vacuum. If you do, the FTP sensor can be damaged.
Signal Current conditions Values Unit FTP SENSOR - 7. Check the parameter(s) below with the HDS for 1 minute.
Signal Current conditions Values Unit FTP SENSOR Does the voltage increase more than 0.2 V (0.1 inHg, 2.5 mmHg)?
YES
Go to step 10.
NO
Go to step 12.
- EVAP canister vent shut valve operation check
-1. Select the EVAP TEST in the INSPECTION MENU, and do the CVS OFF in the SOLENOID TEST with the HDS.
SOLENOID TEST - CVS
Disconnect the EVAP canister vent hose (A) from the EVAP canister vent shut valve port (B), and plug it.
- 3. Apply vacuum to the hose which the vacuum pump/gauge, 0 - 30 inHg, was connected to in step 9-3 until the FTP reads 1.90 V (-0.59 inHg, -15.1 mmHg).
NOTE: Be careful not to exceed the vacuum. If you do, the FTP sensor can be damaged.
Signal Current conditions Values Unit FTP SENSOR - 4. Check the parameter(s) below with the HDS for 1 minute.
Signal Current conditions Values Unit FTP SENSOR Does the voltage increase more than 0.2 V (0.1 inHg, 2.5 mmHg)?
YES
Go to step 11.
NO
- EVAP canister purge line visual check
-1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Check for a poor connection or damaged EVAP canister purge line between the EVAP canister and the EVAP canister purge valve. Also check for damage to the EVAP canister.
Are the line and the EVAP canister OK?
-
YES
Replace these parts.
- FTP sensor O-ring
- EVAP canister vent shut valve case and O-ring
- EVAP canister
NO
Replace or repair the EVAP canister purge line or canister.
-
- Fuel fill pipe and fuel tank vapor recirculation tube visual check
-1. Select the EVAP TEST in the INSPECTION MENU, and do the CVS OFF in the SOLENOID TEST with the HDS.
SOLENOID TEST - CVS
Check for a poor connection or damage to the fuel fill pipe and the fuel tank vapor recirculation tube.
Are the parts and connections OK?
YES
The fuel fill pipe and the fuel tank vapor recirculation tube are OK. Check the fuel tank unit base gasket and the fuel tank.
NO
Repair the damaged parts or connections, or replace the fuel tank if needed.