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 solenoid valve and the EVAP vent solenoid are turned ON, allowing the engine to draw a small vacuum on the entire evaporative emission system. Once the desired vacuum level has been achieved, the EVAP canister purge solenoid valve turns OFF, sealing the system. A small leak in the system will cause DTC P0442 to set.
• | 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 more than 75 kPa. |
• | The intake air temperature (IAT) is between 5°C and 29°C (41°F and 84°F) at engine start-up. |
• | The engine coolant temperature (ECT) is between 5°C and 29°C (41°F and 84°F) at engine start-up. |
• | The intake air temperature (IAT) is not more than 1°C (2°F) more than the engine coolant temperature (ECT) at start-up. |
• | The engine coolant temperature (ECT) is not more than 7°C (12°F) more than the intake air temperature (IAT) 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 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 3 consecutive ignition cycles in which the diagnostic runs a pass. |
• | A history DTC will clear after 40 consecutive warm up cycles without a malfunction. |
• | Use a scan tool to clear the DTCs. |
Although this DTC is considered a type A diagnostic, this DTC acts like a type B diagnostic during certain conditions. Refer to Serial Data Communications . 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 does not report to the diagnostic executive or display on a scan tool. A passing system always reports to the diagnostic executive immediately.
If a DTC P0461 is set along with an EVAP System DTC, the EVAP DTC cannot be considered valid until you repair and clear DTC P0461.
Inspect for the following conditions:
• | Any missing or damaged O-rings at the fuel vapor and the EVAP purge line canister fittings. |
• | A cracked or a punctured EVAP canister. |
• | A damaged source vacuum line, EVAP purge line, EVAP vent hose, or fuel tank vapor line. |
• | A faulty electrical terminal connection at the PCM. Inspect the harness electrical connectors for the following conditions: |
- | Backed-out terminals |
- | Improper mating |
- | Broken locks |
- | Improperly formed connectors |
- | Damaged terminals |
- | A faulty terminal-to-wire connection |
• | A damaged harness -- Inspect the wiring harness for an intermittent open or shorted circuit in the following components: |
- | The EVAP vent solenoid |
- | The EVAP canister purge solenoid valve |
- | The fuel tank pressure sensor |
• | Refer to Evaporative Emission System Cleaning for further procedure. |
The numbers below refer to the step numbers on the Diagnostic Table.
If a vent solenoid or an EVAP canister purge solenoid 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 P0442.
This step tests the fuel tank pressure sensor at the ambient pressure.
This step verifies that the fuel tank pressure sensor accurately reacts to the EVAP system pressure changes.
This step insures proper system integrity.
Step | Action | Value(s) | Yes | No | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | ||||||||||||
2 |
Is DTC P0452, P0453 or P0461 also set? | -- | ||||||||||||
Does the purge valve and vent solenoid click ON and OFF? | -- | |||||||||||||
Is the fuel tank pressure within the specified value range? | -0.32 - +0.32 kPa (-1.28 - +1.28 in. H2O) | |||||||||||||
5 |
Did you find and correct the condition? | -- | Go to DTC P0452 Fuel Tank Pressure Sensor Circuit Low Voltage or | |||||||||||
Important: : Before continuing with this diagnosis, zero the EVAP Pressure and Vacuum gauges on the J 41413 EVAP pressure/purge Diagnostic Station. Then, read the temperature variation instructions. Refer to the tool operating instructions.
Important: Do not exceed the pressure given in the first specified value. Is the fuel tank pressure at the second specified value? | 1.25 kPa (5 in. H2O) .96 kPa (3.85 in. H2O) | Go to DTC P0452 Fuel Tank Pressure Sensor Circuit Low Voltage or | ||||||||||||
7 |
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) | ||||||||||||
8 |
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) | Go to Diagnostic Aids | |||||||||||
9 |
Can the specified vacuum be maintained? | 16.95 kPa (5 in. Hg) | ||||||||||||
10 |
Did you find and correct the condition? | -- | ||||||||||||
11 |
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. Did you complete the replacement? | -- | -- | |||||||||||
12 |
Did you complete the repair? | -- | -- | |||||||||||
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 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) | |||||||||||||
14 |
Does the DTC reset? | -- | System OK |