P0455
DTC P0455: Evaporative Emission Control System Leak Detected (Gross Leak)System Diagram:
TECHNICAL DESCRIPTION
- The fuel tank may be under a slight pressure or vacuum depending on the state of the evaporative emission (EVAP) system. The ECM
- The ECM
- The evaporative emission purge solenoid is activated to apply engine manifold vacuum to the EVAP system.
- When the fuel system develops a vacuum of 2 kPa (0.29 psi), the evaporative emission purge solenoid is turned "off" and the fuel system vacuum is maintained at 2 kPa (0.29 psi).
- The ECM
- The test is stopped when fuel vapor pressure is determined to be too high.
DTC SET CONDITIONS
Check Conditions A: At Start up
- Intake air temperature is 36 °C (97 °F) or less upon engine start up.
- The engine coolant temperature is 36 °C (97 °F) or less upon engine start up.
Check Conditions B: For Test to Run
- Engine coolant temperature is greater than 60 °C (140 °F) When the amount of remaining fuel is 15 - 40 percent of capacity upon engine start up.
- Engine coolant temperature is greater than 20 °C (68 °F) when the amount of remaining fuel is 40 -85 percent of capacity upon engine start up.
- The engine speed is greater than or equal to 1,600 r/min.
- Barometric pressure is greater than 76 kPa (11 psi).
- Volumetric efficiency is between 20 and 70 percent.
- The fuel temperature is 36 °C (97 °F) or less.
- The fuel tank differential pressure sensor output voltage is 1 - 4 volts.
Check Conditions C: For Test to Stop
- The intake air temperature is greater than 5 °C (41 °F).
- When the evaporative emission purge solenoid and evaporative emission ventilation solenoid are closed, the pressure in the fuel tank rises to 451 Pa (0.065 psi) or less and the amount of remaining fuel is 15 - 40 percent of capacity upon engine start up.
- When the evaporative emission purge solenoid and evaporative emission ventilation solenoid are closed, the pressure in the fuel tank rises to 324 Pa (0.047 psi) or less and the amount of remaining fuel is 40 - 85 percent of capacity upon engine start up.
- 10 seconds have elapsed from the start of the previous monitoring.
- Monitoring time: 130 seconds.
Judgment Criteria
- The fuel tank internal pressure is greater than 2 kPa (0.29 psi) after the evaporative emission purge solenoid has been driven when the fuel tank and vapor line were closed
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Loose fuel cap.
- Fuel cap relief pressure is incorrect.
- Fuel overflow limiter valve failed.
- Purge line or vapor line is clogged.
- Fuel tank, purge line or vapor line seal failed.
- Evaporative emission purge solenoid valve failed.
- Evaporative emission ventilation solenoid valve failed.
- Fuel tank differential pressure sensor failed.
- Evaporative emission canister seal is faulty.
- Evaporative emission canister is clogged.
OVERVIEW OF TROUBLESHOOTING
- To determine the cause of DTC P0455, a performance test is needed. The performance test uses a mechanical vacuum gauge and scan tool MB991502 set to the data reading mode for the fuel tank differential pressure sensor (TANK PRES SNSR 73). The mechanical gauge reading is used to verify the scan tool reading. A comparison of the mechanical gauge and scan tool MB991502 determines whether there is a problem in the system.
- Prior to doing the performance test, ensure that the fuel cap is closed securely. Inspect all EVAP system hoses and tubes for damage.
DIAGNOSIS
Required Special Tool:
- MB991502: Scan Tool (MUT-II)
STEP 1. Using scan tool MB991502, check evaporative emission system monitor test.
CAUTION:
- To prevent damage to scan tool MB991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.
- During this test, the ECM
1. Connect scan tool MB991502 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Erase the DTCs using scan tool MB991502.
4. Check that the fuel cap is securely closed. (Tighten until three clicks are heard.)
5. Start the engine.
6. Select "System Test," and press the "YES" key.
7. Select "EVAP Leak Mon," and press the "YES" key
8. During this test, keep the accelerator pedal at the idle position.
9. Keep the engine speed and engine load within the specified range. When the monitor test starts, the "In Progress" item on scan tool MB991502 will change from "NO" to "YES."
10. Turn the ignition switch to the "LOCK" (OFF) position, and disconnect scan tool MB991502.
Q: What is displayed on scan tool MB991502?
"Evap Leak Mon. Completed. Test Passed": The evaporative emission system is working properly at this time. Explain to the customer that an improperly tightened fuel cap can cause the MIL to turn on. Return the vehicle to the customer.
"Evap Leak Mon. Completed. Test Failed and DTCs Set" :A malfunction has been detected during the monitor test. Refer to the Diagnostic Trouble Code Chart and diagnose any other DTCs that are set. If no other DTCs have been set, go to Step 2.
"Evap Lead Mon. Discontinued. Retest again from the first" : The EVAP monitor was interrupted during the test. Turn the ignition switch to the "LOCK" (OFF) position once, and repeat the monitoring from Step 1.
STEP 2. Using scan tool MB991502, check actuator test item 08: Evaporative Emission Purge Solenoid Valve.
CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.
1. Connect scan tool MB991502 to the data link connector.
2. Disconnect hoses B and C from the evaporative emission purge solenoid valve side, and connect the hand vacuum pump to the evaporative emission purge solenoid valve instead of hose C.
3. Turn the ignition switch to the "ON" position.
4. Set scan tool MB991502 to actuator test mode for item 08: Evaporative Emission Purge Solenoid Valve. When the evaporative emission purge solenoid valve is operated, apply a pressure on the hand vacuum pump and confirm that air is blown from the other side nipple.
5. Turn the ignition switch to the "LOCK" (OFF) position.
6. Disconnect the hand vacuum pump, and connect hoses B and C to the evaporative emission purge solenoid valve.
Q: Is the solenoid valve in good condition?
YES: Go to Step 3.
NO: Replace the evaporative emission purge solenoid valve. Go to Step 20.
STEP 3. Check for leaks and clogging in evaporative emission system hoses A through C.Use a hand vacuum pump to test each hose from hose A to hose C.
Q: Are the hoses in good condition?
YES: Go to Step 4.
NO: Replace the damaged hose. Go to Step 20.
STEP 4. Using scan tool MB991502, check the evaporative emission ventilation solenoid and hose F.
CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.
1. Connect scan tool MB991502 to the data link connector.
2. Disconnect hose F from the evaporative emission canister side, and connect a hand vacuum pump.
3. Turn the ignition switch to the "ON" position.
4. Set scan tool MB991502 to actuator test mode for item 29: Evaporative Emission Ventilation Solenoid Valve. While the evaporative emission ventilation solenoid valve is activated, operate the hand vacuum pump and confirm that the solenoid holds vacuum.
5. Turn the ignition switch to the "LOCK" (OFF) position and disconnect scan tool MB991502.
6. Disconnect the hand vacuum pump, and connect hose F to the evaporative emission canister.
Q: Did the evaporative emission ventilation solenoid and hose F hold vacuum?
YES: Go to Step 6.
NO: Go to Step 5.
STEP 5. Check for leaks in the evaporative emission system hose F. Perform a vacuum test using a hand vacuum pump on hose F.
Q: Is the hose in good condition?
YES: Replace the evaporative emission ventilation solenoid. Refer to Evaporative Emission Canister and Fuel Tank Pressure Relief Valve. Go to Step 20.
NO: Replace the damaged hose. Go to Step 20.
STEP 6. Check for leaks and clogging in evaporative emission system hoses D through E.
Perform a vacuum test using a hand vacuum pump on hoses D through E.
Q: Are the hoses in good condition?
YES: Go to Step 7.
NO: Replace the damaged hose. Go to Step 20.
STEP 7. Pressure test the evaporative emission system lines from hose G and P through the fuel tank.
1. Disconnect hose G from the canister, and plug hose G securely.
2. Confirm that the evaporative emission system pressure pump (Miller number 6872A) is operating properly. Perform the self-test as described in the manufacturer's instructions.
3. Remove the fuel cap.
4. Connect the evaporative emission system pressure pump to the fuel filler neck.
5. Pressure test the system to determine whether any leaks are present.
NOTE: The "Pressure test" in this procedure refers to the I/M240 Simulation Test. The eight steps of this test are described in the manufacturer's instructions for the evaporative emission system pressure pump, Miller number 6872A.
6. Disconnect the evaporative emission system pressure pump, and reinstall the fuel cap.
7. Connect hose G to the canister.
Q: Is the evaporative emission system line free of leaks?
YES: Go to Step 14.
NO: Go to Step 8.
STEP 8. Check for vacuum leaks in evaporative emission system hoses G, I, J and K.
1. Remove the fuel filler neck protector. (Refer to Fuel Tank)
2. Perform a leakage test with a hand vacuum pump on each hose from hoses G, I, J and K.
Q: Do the hoses hold vacuum?
YES: Go to Step 9.
NO: replace the damaged hose, and reinstall the fuel filler neck protector. Refer to Fuel Tank. Go to Step 20.
STEP 9. Test check valve A.
1. Check valve A is a one-way check valve.
2. Check valve A should allow air to flow in only one direction.
Q: Does check valve A allow air to pass in one direction only?
YES: Go to Step 10.
NO: Replace check valve A, and reinstall the fuel filler neck protector. Refer to Fuel Tank. Go to Step 20.
STEP 10. Check for vacuum leaks in evaporative emission system hoses H, L, M, N, 0 and P.
1. Remove the fuel tank. (Refer to Fuel Tank)
2. Perform a leakage test with a hand vacuum pump on each hose I, M, N, 0, P and Q.
Q: Are the hoses in good condition?
YES: Go to Step 11.
NO: Replace the damaged hose, and reinstall the fuel tank. Refer to Fuel Tank. Go to Step 20.
STEP 11. Test check valve B.
1. Check valve B is a one-way check valve.
2. Check valve B should allow air to flow in only one direction.
Q: Does check valve B allow air to pass in one direction only?
YES: Go to Step 12.
NO: Replace check valve B, and reinstall the fuel tank and the fuel filler neck protector. Refer to Fuel Tank. Go to Step 20.
STEP 12. Check for leaks in the fuel tank.
1. Visually check for cracks or other leaks in the fuel tank.
NOTE: Carefully check the fuel pump assembly and the inner pressure sensor installation section in the fuel tank.
2. Connect the evaporative emission system pressure pump (Miller number 6872A) to the filler hose.
3. Plug the fuel pump feed nipple, return hose, hose L and hose H connected to the fuel tank.
NOTE: If these items are not securely plugged here, the fuel could leak in the next step.
4. Pressurize the fuel tank with the evaporative emission system pressure pump.
5. In the pressurized state, check for leaks by applying a soapy water solution to each section and look for bubbles.
Q: Is the fuel tank free of leaks?
There are leaks at the fuel pump assembly, the fuel tank differential pressure sensor, leveling valve or the fuel tank rollover valve installation section. : After reassemble the leaked parts, check again that there are no leaks. Then reinstall the fuel tank. Refer to Fuel Tank. Go to Step 20.
There are leaks at the fuel tank. : Replace the fuel tank. Refer to Fuel Tank. Go to Step 20.
There are no leaks. : Reinstall the fuel tank. Refer to, Fuel Tank. Go to Step 13.
STEP 13. Using scan tool MB991502, check the evaporative emission system monitor test.
CAUTION:
- To prevent damage to scan tool MB991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.
- During this test, the ECM
1. Connect scan tool MB991502 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Erase the DTCs using scan tool MB991502.
4. Check the fuel cap is securely closed. (Tighten until three clicks are heard.)
5. Start the engine.
6. Select "System Test," and press the "YES" key.
7. Select "Evap Leak Mon," and press the "YES" key.
8. During the test, keep the accelerator pedal at the idle position.
9. Keep the engine speed and engine load within the specified range. When the monitor test starts, the "In Progress" item on scan tool MB991502 will change from "NO" to "YES."
10. Turn the ignition switch to the "LOCK" (OFF) position. Disconnect scan tool MB991502.
Q: What is displayed on scan tool MB991502?
"Evap Leak Mon. Completed. Test Passed" : The evaporative emission system is working properly at this time. Go to Step 20.
"Evap Leak Mon. Completed. Test Failed and DTCs Set" : Replace the ECM
"Evap Lead Mon. discontinued. Retest again from the first" : The monitor test was interrupted. Turn the ignition switch to the "LOCK" (OFF) position once, and repeat the evaporative emission system monitor test.
STEP 14. Pressure test for clogging in evaporator line from hose G to hose P.
1. Disconnect hose G from the canister side, and plug the hose.
2. Remove the fuel cap.
3. Connect the evaporative emission system pressure pump (Miller number 6872A) to the fuel filler neck and apply pressure.
NOTE: "Pressure test" in this procedure refers to the I/M240 Simulation Test (8 simple steps) described in the evaporative emission system pressure pump (Miller number 6872A) manufacture's instructions located in the lid of the pump box.
4. After it is confirmed that pressure maintained, unplug hose G.
5. Disconnect the evaporative emission system pressure pump, and reinstall the fuel cap.
6. Connect hose G to the evaporative emission canister.
Q: Is air blown from hose G?
YES: Go to Step 20.
NO: Go to Step 15.
STEP 15. Check for clogging in the evaporator line hoses G, I, J and K.
1. Remove the fuel filler neck protector. (Refer to Fuel Tank)
2. The clogging test with a hand vacuum pump on each hose from hoses G, I, J and K.
Q: Are the hoses in good condition?
YES: Go to Step 16.
NO: Replace the damaged hose, and the fuel filler neck protector. Refer to Fuel Tank. Go to Step 20.
STEP 16. Test check valve A.
1. Check valve A is a one-way check valve.
2. Check valve A should allow air to flow in only one direction.
Q: Does check valve A allow air to pass in one direction only?
YES: Go to Step 17.
NO: Replace check valve A, and reinstall the fuel filler neck protector. Refer to Fuel Tank. Go to Step 20.
STEP 17. Check for clogging in the evaporator line from hoses H, L, M, N, 0 and P. Remove the fuel tank. (Refer to Fuel Tank)
Q: Are the hoses in good condition?
YES: Go to Step 18.
NO: Replace the damaged hose, and reinstall the fuel tank. Refer to Fuel Tank. Go to Step 20.
STEP 18. Test check valve B.
1. Check valve B is a one-way check valve.
2. Check valve B should allow air to flow in only one direction.
Q: Does check valve B allow air to pass in one direction only?
YES: Go to Step 19.
NO: Replace check valve B, reinstall the fuel tank and the fuel filler neck protector. Refer to Fuel Tank. Go to Step 20.
STEP 19. Check the evaporative emission canister for leaks and clogging.
1. Disconnect hoses E, F and G from the canister side, and connect a hand vacuum pump to the canister instead of hose E, and plug the other nipples.
2. Apply a pressure on the hand vacuum pump, and confirm that air is maintained.
3. Disconnect the hand vacuum pump, and connect hoses E, F and G to the canister.
Q: Is the evaporative emission canister in good condition?
YES: Go to Step 13.
NO: Replace the canister. Refer to Evaporative Emission Canister and Fuel Tank Pressure Relief Valve. Go to Step 20.
STEP 20. Test the OBD-II drive cycle.
1. Carry out a test drive with the drive cycle pattern. Refer to, Procedure 1 - Evaporative Emission Control System Leak Monitor.
2. Read the DTC.
Q: Is DTC P0455 set?
YES: Go to Step 1.
NO: The procedure is complete.