P0440
P0440-GENERAL EVAP SYSTEM FAILURE
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:
Engine running after a cold start with the difference between ECT and AAT is less than 10° C (19° F). Fuel Level between 12% and 88% full. Manifold vacuum greater than a calculated minimum value. Ambient Temperature between 4° C and 32° C (39° F and 89° F).
- Set Condition:
When the monitor conditions are met, the Powertrain Control Module (PCM) will ramp in purge flow. If the PCM does not sense an ESIM switch closure after a calculated amount of purge flow accumulation, an error is detected. 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 related 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: Allow the vehicle to reach ambient temperature before continuing with this procedure.
NOTE: A loose gas cap could have caused this DTC to set. Make sure the gas cap is tight and in good condition.
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 reach normal operating temperature.
3. With the scan tool, select View DTCs.
NOTE: It may be necessary to drive the vehicle to meet the conditions to set this DTC, try to repeat the conditions in which the fault originally set by reviewing the Freeze Frame data.
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 AND PHYSICAL INSPECTION
1. Turn the ignition off.
2. Perform a visual and physical inspection of the entire Evaporative Emission system.
3. Check for the following conditions:
- Hoses disconnected or left off
- Holes or cracks
- Loose seal points
- Evidence of damaged components
- Incorrect routing of hoses and tubes
- Fuel Cap left off or bad gasket seal
Were any of the above conditions found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
No
- Go To 4
4. EVAPORATIVE VACUUM SUPPLY HOSE INSPECTION
1. Carefully inspect the Evap Purge Solenoid vacuum supply hose for proper routing.
2. Check for a pinched or plugged hose from the throttle body or intake manifold to the Purge Solenoid.
3. Make sure the vacuum port at the throttle body or intake manifold is free from any blockage.
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. EVAP PURGE SOLENOID
NOTE: To continue testing you will need the Evaporative Emission Leak Detector (EELD) 8404A.
WARNING: Keep lit cigarettes, sparks, flames, and other ignition sources away from the test area to prevent the ignition of explosive gases, Keep the test area well ventilated.
1. Connect the red power lead of the EELD to the battery positive terminal and the black ground lead to battery negative terminal.
2. Disconnect the vacuum hoses at the Evap Purge Solenoid.
3. Connect the SMOKE supply tip (black hose) to the "CAN" port on the Evap Purge Solenoid.
4. Set the smoke/air control switch to SMOKE.
5. While still holding the remote smoke/air start button, check to see if smoke is exiting the purge valve. This indicates that there is a leak internal to the purge valve.
NOTE: This is an optional method of checking the purge valve for leaks if the EELD is unavailable.
6. Disconnect the Smoke supply tip from the vacuum supply hoses at the Evap Purge Solenoid.
7. Using a hand vacuum pump, apply 10 inches of Hg to the "CAN" side of the Evap Purge Solenoid.
8. Observe the vacuum gauge for at least 15 seconds.
Is smoke visible from the Evap Purge Solenoid or NOT hold a vacuum?
Yes
- Replace the Evap Purge Solenoid.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 6
6. ESIM SWITCH STATE
1. Turn the ignition off.
2. Connect the previously disconnected vacuum hose.
3. Disconnect the ESIM Switch harness connector.
4. Ignition on, engine not running.
5. Monitor the ESIM Switch state on the scan tool.
6. Carefully connect a jumper wire between the (K107) ESIM Signal circuit and the (Z910) Ground circuit in the ESIM Switch harness connector.
7. Monitor the ESIM Switch state on the scan tool.
Did the Switch change from OPEN to CLOSED when the jumper wire was installed?
Yes
- Go To 9
No
- Go To 7
NOTE: Remove the jumper wire before continuing.
7. EXCESSIVE RESISTANCE IN THE (K107) ESIM SIGNAL CIRCUIT
1. Turn the ignition off.
2. Disconnect the C3 PCM harness connector.
CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install PCM Pinout Box 8815 to perform diagnosis.
3. Measure the resistance of the (K107) ESIM Signal circuit from the ESIM harness connector to the appropriate terminal of the PCM Pinout Box 8815.
Is the resistance below 5.0 Ohms?
Yes
- Go To 8
No
- Repair the excessive resistance in the (K107) ESIM Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
8. EXCESSIVE RESISTANCE IN THE (Z910) GROUND CIRCUIT
1. Using a 12-volt test light connected to B+, probe the (Z910) Ground circuit in the ESIM harness connector.
NOTE: The test light should illuminate brightly. Compare the brightness to that of a direct connection to B- (ground).
Does the test light illuminate brightly?
Yes
- Go To 14
No
- Repair the excessive resistance in the (Z910) Ground circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
9. VERIFY EVAPORATIVE EMISSION LEAK
WARNING: Keep lit cigarettes, sparks, flames, and other ignition sources away from the test area to prevent the ignition of explosive gases. Keep the test area well ventilated. Failure to do so may result in possible serious or fatal injury.
1. Turn the ignition off.
2. To continue testing you will need the Evaporative Emission Leak Detector (EELD) 8404A.
NOTE: The fuel tank should have between 20% and 80% of fuel tank capacity to properly test the Evaporative system.
3. Connect the red power lead of EELD to the battery positive terminal and the black ground lead to battery negative terminal.
4. Block the vent hose of the Evaporative Canister.
5. Connect shop air to the EELD.
6. Set the smoke/air control switch to AIR.
7. Insert the tester's AIR supply tip (clear hose) into the.040 orifice on the tester's control panel.
8. Press the remote smoke/air start button.
9. Position the red flag on the air flow meter so it is aligned with the indicator ball.
10. When the calibration is complete, release the remote button. The EELD flow meter is now calibrated in liters per minute.
11. Install the service port adapter 8404-14 on the vehicle's service port (if equipped) or install the adapter 8404-ADP into the filter line.
12. Connect the Air supply hose from the EELD to the service port (if equipped) or to the adapter 8404-ADP.
13. Press the remote button to activate AIR flow.
14. Compare the flow meter indicator ball reading to the red flag.
15. ABOVE the red flag indicates a leak present.
16. BELOW the red flag indicates a sealed system.
Is the indicator ball above the red flag?
Yes
- Go To 10
No
- Go To 12
10. EVAPORATIVE EMISSION LEAK DETECTION
NOTE: A thorough visual inspection of the Evaporative system hoses, tubes and connections may save time in your diagnosis. Look for any physical damage or signs of wetness at connections. The strong smell of fuel vapors may aid diagnosis also.
1. Remove the Air supply hose from the service port or the adapter 8404-ADP.
2. Connect the SMOKE supply tip (black hose) to the service port (if equipped) or to the adapter 8404-ADP.
3. Set the smoke/air control switch to SMOKE.
NOTE: The flow meter indicator ball will not move at this point.
4. Press the remote smoke/air start button.
NOTE: Make sure that smoke has filled the Evaporative system by continuing to press the remote smoke/air start button, remove the vehicle fuel cap and wait for the smoke to exit. Once smoke is indicated reinstall the fuel cap.
NOTE: For optimal performance, introduce smoke into the system for an additional 60 seconds; continue introducing smoke at 15 second intervals, as necessary.
5. While still holding the remote smoke/air start button, use the white light 8404-CLL to follow the Evaporative system path and look for the source of the leak indicated by exiting smoke.
6. If a leak is concealed from view (i.e., top of fuel tank), release the remote smoke/air start button and use the ultraviolet (UV) black light 8404-UVL and the yellow goggles 8404-20 to look for residual traces of dye that are left behind by the smoke.
7. The exiting smoke deposits a residual fluid that is either bright green or bright yellow in color when viewed with a UV light.
NOTE: The Evaporative System is divided into three zones. A leak from any of these zones can cause this DTC to set. The lists below specify the possible leak points in that specific zone. For further assistance see the Zone Identification Charts below.
ZONE 1
1. Fuel Cap
2. Recirculation Check Valve
3. Vapor Recirculation Line
4. Signal Vapor Line for FVM
5. Flow Management Valve
6. Fuel Tank to Canister Vapor Line
7. Fuel Tank Vent (Check Valve)
8. Vapor Line to Canister
9. Flow Control Orifice
10. Control Valve
11. Liquid Trap
12. Fuel Tank
13. Check valve
14. Fuel Fill Tube to Tank connector
15. Fuel Fill Tube
ZONE 2
1. Filter
2. ESIM switch
3. Canister Vent Line
4. Evaporative Canister
5. Chassis Purge Valve
6. Fuel Tank to Canister Vapor Line connection
7. Evaporative Purge connection
ZONE 3
1. Evaporative Purge Vacuum Line
2. Connection to Chassis Line
3. Connection to Canister
4. Chassis Purge Line
5. Evaporative Purge Vacuum Line
6. Connection to Evaporative Purge Harness
7. Chassis Evaporative Purge Line connection to Engine Vacuum
8. Evap Purge Valve
9. Service Port
NOTE: Carefully inspect the vent side of the Evaporative Canister. Due to the filtering system in the canister the smoke or dye may or may not be visible. Introducing smoke into the filtered side of the canister may assist in locating the leak.
Select the appropriate response from the list below:
A leak was found at the gas cap or fuel filler tube.
- Go To 11
A leak was found in one or more of the Evaporative System zones.
- If the leak is at a hose connection, remove the hose then reconnect the hose and check for a leak again. All other leaks repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No leaks were detected.
- Go To 12
11. LEAK AT GAS CAP
1. Remove the SMOKE supply tip (black hose) from the service port (if equipped) or to the adapter 8404-ADP.
2. Install Leak Check Adapter 8382 (1/4 turn cap) or Fuel Tank Adapter 6922 (screw on cap) and Leak Check Adapter 8399 (secondary seal depressor) and repeat step 10.
NOTE: The gas cap adapter is being used as a known good cap.
Was a leak found at the gas cap adapter?
Yes
- Replace the Fuel Filler tube assembly.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Replace the gas cap.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
12. 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 between the Fuel Tank and the Evap 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 13
13. EVAPORATIVE SYSTEM INTEGRITY MONITOR SWITCH
1. Use the wiring diagram/schematic as a guide, inspect the wiring and connections between the ESIM Switch and the 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 ESIM Switch and the Powertrain Control Module connectors.
4. Look for any broken, bent, pushed out or corroded terminals.
5. Perform any Technical Service Bulletins that may apply.
Were any problems found?
Yes
- Repair and Replace as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Replace the ESIM Switch.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
.
14. 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.