GM Service Manual Online
For 1990-2009 cars only

System Description

This DTC tests for continuous intake manifold vacuum flow to the Evaporative Emission (EVAP) System. The control module seals the EVAP system by commanding the EVAP canister purge solenoid valve Closed and the EVAP canister vent solenoid valve Closed. The control module monitors the fuel tank pressure (FTP) sensor to determine if a vacuum is being drawn on the EVAP system. If vacuum in the EVAP system is more than a predetermined value within a predetermined time, this DTC sets.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0441 Evaporative Emissions (EVAP) System Continuous Purge Flow

Conditions for Running the DTC

    • DTCs P0106, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0131, P0132, P0133, P0137, P0138, P0140, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P0273, P0274, P0276, P0277, P0300, P0402, P0404, P0405, P0406, P0452, P0453, P0462, P0463, P0501, and P2422 are not set.
    • The ignition 1 voltage is between 11-16 volts.
    • The barometric pressure (BARO) is more than 72 kPa.
    • The engine coolant temperature (ECT) is more than 70°C (158°F).
    • The estimated ambient air temperature is more than 9.75°C (50°C).
    • The purge enable time is more than 15 seconds.
    • The engine run time is more than 590 seconds.
    • The Fuel Tank Pressure is more than -1 Kpa and less than .3 Kpa.
    • The fuel level is between 14-87 percent.
    • The engine is idling.
    • The vehicle speed is less than 2 km/h (1 mph).
    • DTC P0441 runs once an ignition cycle when the above conditions are met.

Conditions for Setting the DTC

The FTP sensor indicates vacuum during a non-purge condition.

Action Taken When the DTC Sets

    • The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC

    • The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
    • Clear the MIL and the DTC with a scan tool.

Step

Action

Values

Yes

No

Schematic Reference: Evaporative Emissions Hose Routing Diagram

1

Did you perform the Diagnostic System Check - Engine Controls?

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Go to Step 2

Go to Diagnostic System Check - Engine Controls

2

  1. Turn the ignition OFF.
  2. Disconnect the EVAP vent line from the vent solenoid, and seal it, using a suitable plug or a plug from the J 41413-300 EVAP Cap/Plug Kit.
  3. Important: Additional DTCs will set with the EVAP solenoid disconnected.

  4. Disconnect the harness connector of the EVAP canister purge solenoid valve.
  5. Start the engine.
  6. Increase the engine speed to 1,200-1,500 RPM.
  7. Observe the fuel tank pressure sensor in H2O with a scan tool.

Is the fuel tank pressure sensor parameter within the specified value?

-1 to +1 H2O

Go to Diagnostic Aids

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Disconnect the evaporative emission (EVAP) purge pipe from the EVAP canister purge solenoid valve.
  3. Turn ON the ignition, with the engine OFF.
  4. Observe the fuel tank pressure sensor in H2O with a scan tool.

Is the fuel tank pressure sensor parameter within the specified range?

-1 to +1 H2O

Go to Step 4

Go to Step 5

4

Replace the EVAP purge solenoid. Refer to Evaporative Emission Canister Purge Solenoid Valve Replacement .

Did you complete the replacement?

--

Go to Step 6

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5

Replace the fuel tank pressure (FTP) sensor.

Did you complete the replacement?

--

Go to Step 6

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6

  1. Connect the EVAP purge pipe to EVAP canister purge solenoid valve.
  2. With the vent still plugged and the EVAP purge solenoid disconnected, start the engine.
  3. Increase the engine speed to 1,200-1,500 RPM.
  4. Observe the fuel tank pressure sensor parameter with a scan tool.

Is the fuel tank pressure sensor parameter within the specified range?

-1 to +1 H2O

Go to Step 7

Go to Step 2

7

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

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Go to Diagnostic Trouble Code (DTC) List

System OK