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P0441






P0441-EVAP PURGE SYSTEM PERFORMANCE





For a complete wiring diagram, refer to the Wiring Information.

Theory of Operation

The Evaporative Purge Monitor tests the integrity of the hoses/tube between the throttle body/intake and the fuel tank. The monitor is a two stage test and runs only after the Evaporative system passes the small leak test. Stage one is non-intrusive. The Powertrain Control Module (PCM) monitors the purge vapor ratio and the Evaporative System Integrity Monitor (ESIM) Switch closed ratio. If the purge vapor ratio is above a calculated value, the monitor passes. If the ESIM Switch closed ratio is greater than calculated value when purge flow is greater than a minimum value, the monitor passes. Stage two is an intrusive test and runs only if stage one does not pass. The PCM commands the purge solenoid to flow at a specified rate to force the purge vapor ratio to update. The ratio is compared to a calibrated specification. If it is less than specified, a one trip failure is recorded. This test can detect if the purge hose is off, obstructed or the purge valve is not operational.

- When Monitored:
After the Evaporative System small leak test has passed, with the engine running, ambient temperature between 4° C (39° F) and 35° (95° F), with the engine at idle after a calibrated amount of drive time has accumulated.

- Set Condition:
If the Powertrain Control Module (PCM) detects that the purge vapor ratio and the ESIM Switch closed ratio are below a calculated value, the PCM commands the purge solenoid to flow at a specified rate to update the purge vapor ratio. If the ratio remains below a specified value, a one trip failure is recorded. Two Trip Fault. Three good trips to turn off the MIL.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

1. VEHICLE HISTORY AND SERVICE BULLETIN INVESTIGATION
1. Ignition on, engine not running.
2. With the scan tool, select View DTCs. Record the Freeze Frame data if any DTCs are present.
3. Whether or not any DTCs are Active you will want to check the following items which may assist in repairing the customer's complaint successfully.
4. Check the vehicles repair history.
5. If the vehicle has a repair history that pertains to the customer's current complaint, review the repair.
6. Inspect the vehicle for any aftermarket accessories that may have been installed incorrectly.
7. Check for any service bulletin(s) related to the customer's complaint or DTCs.
8. If a service bulletin applies, follow the instructions per the service bulletin.

Choose the following scenario that best applies.

The service bulletin repaired the customer's complaint.

- Testing complete.

A DTC is present, no service bulletins apply or the service bulletin didn't repair the customer's complaint.

- Go To 2

2. ACTIVE DTC

NOTE: If P0443 is set along with this DTC, perform the diagnostic procedure for P0443 before continuing with this test. P0443

NOTE: If the customer is experiencing an early fuel shut off during the fuel filling process along with P0440, P0441 and P0452 setting, you need to check for restrictions in the Evaporative Purge tubes/hoses as well as the Fresh Air Filter before continuing.

1. Start the engine.
2. Allow the engine to idle.
3. Using the scan tool, perform the ESIM FORCED MONITOR TEST. Allow the test to complete.
4. With the scan tool, select View DTCs.

NOTE: If any other DTC sets, active or pending, perform the diagnostic procedure for that DTC before proceeding with this test.

Is the DTC Active or Pending at this time?

Yes

- Go To 3

No

- Perform the INTERMITTENT CONDITION diagnostic procedure. Intermittent Condition Test.

3. VISUAL INSPECTION
Inspect the Evaporative System for any of the following conditions:

- Holes or cracks
- Loose seal points
- Damaged or missing components
- Incorrect routing of hoses and tubes
- Loose or missing Fuel Cap
- Damaged or missing Fuel Cap seal
- Improper installation of the Fuel Cap
- Damaged Locking tabs on the Fuel Cap and/or filler tube
- Damaged seal points on the Fuel Cap and/or filler tube

Were any problems found?

Yes

- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 4

4. INSUFFICIENT VACUUM SUPPLY TO THE EVAP PURGE SOLENOID
1. Turn the ignition off.
2. Carefully inspect the Evap Purge Solenoid vacuum supply hose for proper routing.
3. Check for a pinched or plugged hose from the throttle body or intake manifold to the Purge Solenoid.
4. Inspect the vacuum port at the throttle body or intake manifold for any damage or obstructions.

Were any problems found?

Yes

- Repair the vacuum supply hose/tube as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go To 5

5. EVAPORATIVE PURGE HOSE/TUBE AND FRESH AIR FILTER OBSTRUCTION
1. Inspect the Evaporative Purge hose/tube for proper routing and installation between the Evap Purge Solenoid and the Fuel Tank and between the Fuel Tank and the Evaporative Purge Canister.
2. Make sure the hose/tube and fresh air filter are not damaged, kinked and free from any obstructions.

Were any problems found?

Yes

- Repair or replace as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 6

6. EVAP PURGE SOLENOID

NOTE: After disconnecting the Evap Purge Solenoid vacuum connections, inspect the lines and solenoid for signs of contamination.

1. Using a hand vacuum pump, apply 10 inches of Hg to the "CAN" side of the Evap Purge Solenoid.

NOTE: The solenoid should hold vacuum for a minimum of 15 seconds.

2. Ignition on, engine not running.
3. With the scan tool, actuate the Evap Purge Solenoid to the ON position.

NOTE: The vacuum should drop when the solenoid is actuated.

Does the solenoid function as described above?

Yes

- Go To 7

No

- Replace the Evap Purge Solenoid.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

7. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Evap Purge Solenoid Assembly, ESIM switch and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Switch, Solenoid and the Powertrain Control Module connectors.
4. Perform any Technical Service Bulletins that may apply.

Were there any problems found?

Yes

- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Replace and program the Powertrain Control Module.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.