The evaporative system includes the following components:
• | The fuel tank |
• | The EVAP vent solenoid |
• | The fuel tank pressure sensor |
• | The fuel pipes and hoses |
• | The fuel vapor lines |
• | The fuel cap |
• | The EVAP canister |
• | The purge lines |
• | The EVAP canister purge solenoid valve |
• | The EVAP service port |
The evaporative emission (EVAP) system is checked by applying vacuum to the EVAP system and by monitoring for a vacuum decay. The Powertrain Control Module (PCM) monitors the vacuum level through the fuel tank pressure sensor signal. At an appropriate time, the EVAP canister purge valve and the EVAP vent solenoid are turned ON, allowing the engine to draw a small vacuum on the entire evaporative emission system. After the desired vacuum level has been achieved, the EVAP canister purge valve will turn OFF, sealing the system. DTC P0440 will set because the PCM is not detecting the expected vacuum. This can be caused by the following components with the conditions listed below:
• | The fuel cap for the following conditions: |
- | Missing |
- | Malfunctioning |
- | Incorrect |
• | The fuel tank pressure sensor for the following conditions: |
- | Disconnected |
- | Malfunctioning |
• | The EVAP purge line for the following conditions: |
- | Disconnected |
- | Damaged |
- | Pinched |
- | Blocked |
• | The EVAP vent hose for the following conditions: |
- | Disconnected |
- | Damaged |
• | The fuel tank vapor line for the following conditions: |
- | Disconnected |
- | Damaged |
- | Pinched |
- | Blocked |
• | The EVAP canister purge solenoid valve for the following conditions: |
- | Disconnected |
- | Malfunctioning |
• | The EVAP vent solenoid for the following conditions: |
- | Disconnected |
- | Malfunctioning |
• | An open ignition feed circuit to the following components: |
- | EVAP vent valve |
- | Purge solenoid |
• | A damaged EVAP canister |
• | A leaking fuel sender assembly O-ring |
• | A leak in the following items: |
- | Fuel tank |
- | Fuel filler neck |
• | DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0125, P0131, P0132, P0133, P0134, P0452, P0453, P0502, P0503, P0601, P0602, P1621 and P1133 are not set. |
• | The BARO is greater than 75 kPa. |
• | The intake air temperature is between 5°C and 29°C (41°F and 84°F) at engine start up. |
• | The engine coolant temperature is between 5°C and 29°C (41°F and 84°F) at engine start up. |
• | The Intake Air Temperature is not more than 1°C (2°F) greater than the Engine Coolant Temperature at start up. |
• | The Engine Coolant Temperature is not more than 7°C (12°F) greater than the Intake Air Temperature at start up. |
• | The fuel tank level is between 26 percent and 74 percent. |
• | The TP sensor is between 7 percent and 35 percent. |
• | The EVAP solenoid is at 40 percent PWM. |
The EVAP system is unable to detect vacuum during the diagnostic test.
• | The Malfunction Indicator Lamp (MIL) will illuminate. |
• | The PCM will record the operating conditions at the time that the diagnostic fails. The Freeze Frame and Failure Records buffers will store this information. |
• | A history DTC stores. |
• | The MIL will turn OFF after one ignition cycle in which the diagnostic runs a pass. |
• | The freeze Frame information and the history DTC will clear after one ignition cycle in which the diagnostic runs without a fault. |
Although this DTC is considered a type A diagnostic (refer to Serial Data Communications ), this DTC acts like a type B diagnostic under certain conditions. Whenever this diagnostic reports that the system has passed or if the battery is disconnected, the diagnostic must fail twice before setting a DTC. The initial failure is not reported to the diagnostic executive or displayed on a scan tool. A passing system always reports to the diagnostic executive immediately.
If a DTC P0461, P0462 or P0463 is set along with an EVAP System DTC, the EVAP DTC cannot be considered valid until you repair and clear DTC P0461, P0462 and P0463.
Check the following components for the indicated conditions:
• | The fuel cap for the following conditions: |
- | Missing |
- | Damaged |
- | Incorrect |
• | The O-rings at the EVAP canister fuel vapor and purge line fittings for the following conditions: |
- | Missing O-rings |
- | Damaged O-rings |
• | The EVAP canister for the following conditions: |
- | Cracked |
- | Punctured |
• | The following components for damage or disconnects: |
- | EVAP purge line |
- | Vent hose |
- | Fuel tank vapor line |
- | Source vacuum line |
• | A poor electrical connection at the PCM. Inspect the harness connectors for the following conditions: |
- | Backed out terminals |
- | Improper mating |
- | Broken locks |
- | Improperly formed or damaged terminals |
- | Poor terminal to wire connection |
• | A damaged wiring harness. Inspect the wiring harness to the following components for an intermittent open circuit or a shorted circuit: |
- | EVAP vent solenoid |
- | EVAP canister purge solenoid valve |
- | Fuel tank pressure sensor |
• | Verify that the lines are not restricted in the following components: |
- | Plugged vacuum source |
- | EVAP purge line |
- | Fuel tank vapor line |
• | Refer to Evaporative Emission System Cleaning for further procedure. |
The number(s) below refer(s) to the step number(s) on the Diagnostic Table.
The Powertrain OBD System Check prompts you to complete some of the basic checks and to store the freeze frame and failure records data on the scan tool if applicable. This creates an electronic copy of the data captured when the malfunction occurred. The scan tool stores this data for later reference.
If a vent solenoid or an EVAP canister purge valve electrical malfunction is present, the purge system will not operate correctly. Repairing the electrical malfunction will very likely correct the condition that set DTC P0440.
This step checks the fuel tank pressure sensor at the ambient pressure.
This step determines whether or not the EVAP system is sealed sufficiently in order to be pressurized. If not, you must locate and correct the large leak before continuing with the diagnosis.
This step verifies that the fuel tank pressure sensor accurately reacts to the EVAP system pressure changes.
This step checks for a stuck closed EVAP canister purge solenoid valve.
This step ensures that a sufficient source vacuum is present at the EVAP canister purge solenoid valve.
This step insures a proper system integrity.
Step | Action | Value(s) | Yes | No | ||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | |||||||||||||||||||
2 |
Is DTC P0452, P0453 or P0461 also set? | -- | Go to Component DTC table | |||||||||||||||||
3 |
Was a loose, malfunctioning or a missing fuel cap found? | -- | ||||||||||||||||||
Does the purge valve and the vent solenoid click when commanded ON and OFF? | -- | |||||||||||||||||||
Is the Fuel Tank Pressure at the specified value? | 0 mm Hg -2.4-2.4 mm Hg (-1.28-1.28 in H2O) | |||||||||||||||||||
6 |
Was a repair necessary? | -- | Go to DTC P0452 Fuel Tank Pressure Sensor Circuit Low Voltage or | |||||||||||||||||
Important:: Before continuing with this diagnosis, zero the EVAP Pressure and the Vacuum gauges on the J 41413 EVAP pressure/purge Diagnostic Station . Also, read the temperature variation instructions. (refer to the tool operating instructions).
Important: Do not exceed the pressure in the specified value. Can the specified value be achieved? | 1.24 kPa (5 in H2O) | |||||||||||||||||||
Does the Fuel Tank Pressure decrease to less than the second specified value within 2 minutes? | 1.24 kPa (5 in H2O) 12 mm Hg (7.2-16.8 mm Hg) (3.85-8.99 in H2O) | |||||||||||||||||||
9 |
Important: Review the temperature variation instructions included with the J 41413 EVAP pressure/purge Diagnostic Station before performing this step.
Important: Do not exceed the pressure given in the first specified value. Does the pressure decrease to less than the second specified value within 2 minutes? | 3.74 kPa (15 in H2O) 2.49 kPa (10 in H2O) | ||||||||||||||||||
10 |
Can vacuum be achieved and maintained at the specified value? | 17 kPa (5 in Hg) | ||||||||||||||||||
11 |
Was a problem found? | -- | Go to DTC P0452 Fuel Tank Pressure Sensor Circuit Low Voltage or | |||||||||||||||||
Does the EVAP canister purge valve release the vacuum? | 34 kPa (10 in Hg) | |||||||||||||||||||
13 |
Did the vacuum gauge read greater than the second specified value when the throttle was snapped open and then closed? | 2,500 RPM 33.86 kPa (10 in Hg) | Go to Diagnostic Aids | |||||||||||||||||
Was a repair necessary? | -- | |||||||||||||||||||
15 |
Was a repair necessary? | -- | ||||||||||||||||||
16 |
Is the action complete? | -- | -- | |||||||||||||||||
17 |
Notice: The EVAP canister may have released carbon particles which caused this part to fail and may cause damage to other components. Check the EVAP canister for loose carbon before returning the vehicle to service. Is the action complete? | -- | -- | |||||||||||||||||
18 |
Is the action complete? | -- | -- | |||||||||||||||||
19 |
Notice: The EVAP canister may have released carbon particles which caused this part to fail and may cause damage to other components. Check the EVAP canister for loose carbon before returning the vehicle to service. Is the action complete? | -- | -- | |||||||||||||||||
Important: Review the temperature variation instructions included with J 41413 EVAP pressure/purge Diagnostic Station before performing this step.
Important: Do not exceed the pressure given in the first specified value. Does the pressure decrease to less than the second specified value within 2 minutes? | 3.74 kPa (15 in H2O) 2.49 kPa (10 in H2O) | |||||||||||||||||||
21 |
Does the scan tool indicate that the diagnostic ran and passed? | -- | ||||||||||||||||||
22 | Check to see if any additional DTC are set. Does the scan tool display any DTCs that you have not diagnosed? | -- | Go to applicable DTC table | System OK |