DTC P04F1: EVAP System Low Purge Flow 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
NOTE: Before you troubleshoot, review the general troubleshooting information - Refer to: How to Troubleshoot the Fuel and Emissions Systems (2017) .
| DTC Description | Confirmed DTC | Pending DTC |
|---|---|---|
| P04F1 EVAP System Low Purge Flow Detected |
DTC (PGM-FI)
- Problem verification
-1. Turn the vehicle to the ON mode.
- 2. Clear the DTC with the HDS.
- 3. 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, the EVAP canister purge valves, 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 result of the FUNCTION TEST is OK, but the DTC P04F1 is stored again, go to step 2.
NO
The failure is duplicated. Go to step 2
- EVAP canister purge port check 1
-1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Remove the intake air duct A/B.
- 3. Disconnect the hose (A) of EVAP canister purge valve 1 (B) from the intake manifold, then connect a vacuum pump/gauge, 0-30 inHg, to the intake manifold as shown.
- 4. Apply vacuum to the hose.
Does it hold vacuum?
YES
Remove the blockage from the EVAP canister purge port at the intake manifold.
NO
Go to step 3.
- EVAP canister purge port check 2
-1. Disconnect the hose (A) of EVAP canister purge valve 2 (B) from the throttle body, then connect the vacuum pump/gauge, 0-30 inHg, to the throttle body as shown.
- 2. Apply vacuum to the hose.
Does it hold vacuum?
YES
Remove the blockage from the EVAP canister purge port at the throttle body.
NO
Go to step 4.
- EVAP canister purge valve 1 check
-1. Connect a T-fitting (A), a vacuum gauge, and the vacuum pump/gauge, 0 - 30 inHg, to the hose (B) of EVAP canister purge valve 1 (C) as shown.
- 2. Turn the vehicle to the ON mode.
- 3. Apply about 2 kPa (0.6 inHg, 15 mmHg) of vacuum to the hose, and wait for a minute.
- 4. Select the EVAP TEST in the INSPECTION MENU, and do the PCS 1 ON in the SOLENOID TEST with the HDS.
SOLENOID TEST - PCS1
Does it hold vacuum, then release?
YES
EVAP canister purge valve 1 is OK, go to step 5.
NO (Does not hold vacuum)
Check for leakage of the hose between EVAP canister purge valve 1 and the intake manifold. If the hose is OK, replace EVAP canister purge valve 1 .
NO (Does not release vacuum)
Check for a blockage in the hose between EVAP canister purge valve 1 and the intake manifold. If the hose is OK, replace EVAP canister purge valve 1 .
- EVAP canister purge valve 2 check
-1. Select the EVAP TEST in the INSPECTION MENU, and do the PCS 1 OFF in the SOLENOID TEST with the HDS.
SOLENOID TEST - PCS1
Remove the T-fitting, the vacuum gauge, and the vacuum pump/gauge, 0 - 30 inHg, and reconnect the hose to EVAP canister purge valve 1.
- 3. Connect the T-fitting (A), the vacuum gauge, and the vacuum pump/gauge, 0 - 30 inHg, to the hose (B) of EVAP canister purge valve 2 (C) as shown.
- 4. Apply about 2 kPa (0.6 inHg, 15 mmHg) of vacuum to the hose, and wait for a minute.
- 5. Select the EVAP TEST in the INSPECTION MENU, and do the PCS 2 ON in the SOLENOID TEST with the HDS.
SOLENOID TEST - PCS2
Does it hold vacuum, then release?
YES
EVAP canister purge valve 2 is OK, go to step 6.
NO (Does not hold vacuum)
Check for leakage of the hose between EVAP canister purge valve 2 and the throttle body. If the hose is OK, replace EVAP canister purge valve 2 .
NO (Does not release vacuum)
Check for a blockage in the hose between EVAP canister purge valve 2 and the throttle body. If the hose is OK, replace EVAP canister purge valve 2 .
- EVAP canister purge line check 1
-1. Select the EVAP TEST in the INSPECTION MENU, and do the PCS 2 OFF in the SOLENOID TEST with the HDS.
SOLENOID TEST - PCS2
Remove the T-fitting, the vacuum gauge, and the vacuum pump/gauge, 0 - 30 inHg, and reconnect the hose to EVAP canister purge valve 2.
- 3. Disconnect the hose (A) from the 3-way joint (B), then connect the T-fitting (C), the vacuum gauge, and the vacuum pump/gauge, 0 - 30 inHg, to the 3-way joint as shown.
- 4. Apply about 2 kPa (0.6 inHg, 15 mmHg) of vacuum to the hose, and wait for a minute.
- 5. Select the EVAP TEST in the INSPECTION MENU, and do the PCS 1 ON in the SOLENOID TEST with the HDS.
SOLENOID TEST - PCS1
Does it hold vacuum, then release?
YES
Go to step 7.
NO (Does not hold vacuum)
Check for leakage between the 3-way joint and EVAP canister purge valve 1.
NO (Does not release vacuum)
Check for a blockage between the 3-way joint and EVAP canister purge valve 1.
- EVAP canister purge line check 2
-1. Select the EVAP TEST in the INSPECTION MENU, and do the PCS 1 OFF in the SOLENOID TEST with the HDS.
SOLENOID TEST - PCS1
- 2. Apply about 2 kPa (0.6 inHg, 15 mmHg) of vacuum to the hose, and wait for a minute.
- 3. Select the EVAP TEST in the INSPECTION MENU, and do the PCS 2 ON in the SOLENOID TEST with the HDS.
SOLENOID TEST - PCS2
Does it hold vacuum, then release?
YES
Go to step 8.
NO (Does not hold vacuum)
Check for leakage between the 3-way joint and EVAP canister purge valve 2.
NO (Does not release vacuum)
Check for a blockage between the EVAP canister and EVAP canister purge valve 2.
- EVAP canister purge line check 3
-1. Select the EVAP TEST in the INSPECTION MENU, and do the PCS 2 OFF in the SOLENOID TEST with the HDS.
SOLENOID TEST - PCS2
Remove the T-fitting, the vacuum gauge, and the vacuum pump/gauge, 0 - 30 inHg, and reconnect the hose to the 3-way joint.
- 3. Disconnect the EVAP canister purge line (A) from the EVAP canister (B), then connect the T-fitting (C), the vacuum gauge, and the vacuum pump/gauge, 0 - 30 inHg, to the EVAP canister purge line as shown.
- 4. Apply about 2 kPa (0.6 inHg, 15 mmHg) of vacuum to the hose, and wait for a minute.
- 5. Select the EVAP TEST in the INSPECTION MENU, then do the PCS 1 and PCS 2 ON in the SOLENOID TEST with the HDS.
SOLENOID TEST - PCS1 and PCS2
Does it hold vacuum, then release?
YES
Go to step 9.
NO (Does not hold vacuum)
Check for leakage between the EVAP canister and the 3-way joint.
NO (Does not release vacuum)
Check for a blockage between the EVAP canister and the 3-way joint.
- EVAP canister vent line check
-1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Disconnect the fuel tank vapor recirculation tube (A) and the EVAP canister vent hose (B) from the EVAP canister (C), and plug the ports (D).
- 3. Disconnect the hose (A) from the EVAP canister (B), then connect the T-fitting (C), the vacuum gauge, and the vacuum pump/gauge, 0 - 30 inHg, to the EVAP canister as shown.
- 4. Slowly apply about 2 kPa (0.6 inHg, 15 mmHg) of vacuum to the hose, then remove the plug from the EVAP canister vent port.
NOTE: Be careful not to exceed the vacuum. If you do, the FTP sensor can be damaged.
Does it hold vacuum, then release?
YES
Go to step 10.
NO (Does not hold vacuum)
NO (Does not release vacuum)
Go to step 11.
- FTP sensor performance check
-1. Remove the T-fitting, the vacuum gauge, and the vacuum pump/gauge, 0 - 30 inHg, and reconnect the hoses.
- 2. Remove the FTP sensor with its connector connected.
- 3. Connect the T-fitting (A) to the vacuum gauge and the vacuum pump/gauge, 0 - 30 inHg, to the FTP sensor (B) as shown.
- 4. Turn the vehicle to the ON mode.
- 5. Check and record the FTP sensor reading in the DATA LIST with the HDS.
Signal Current conditions Values Unit FTP SENSOR - 6. Slowly apply about 1.3 kPa (0.4 inHg, 10 mmHg) of vacuum to the hose.
NOTE: Be careful not to exceed the vacuum. If you do, the FTP sensor can be damaged.
- 7. Check the FTP SENSOR in the DATA LIST with the HDS.
Signal Current conditions Values Unit FTP SENSOR Does the value change?
YES
Check for a blockage in the EVAP canister vent hose.
NO
- EVAP canister vent shut valve operation check
-1. Remove the EVAP canister vent shut valve from the EVAP canister.
- 2. Connect the 2P connector to the EVAP canister vent shut valve.
- 3. Turn the vehicle to the ON mode.
- 4. Select EVAP TEST in the INSPECTION MENU, and do the CVS ON in the SOLENOID TEST with the HDS.
SOLENOID TEST - CVS
Check the EVAP canister vent shut valve (A) operation.
Is the valve free of corrosion, and does it operate properly?
YES
NO