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.

The following table illustrates the relationship between the ON and OFF states, and the Open or Closed states of the EVAP canister purge and vent solenoid valves.

Control Module Command

EVAP Canister Purge Solenoid Valve

EVAP Canister Vent Solenoid Valve

ON

Open

Closed

OFF

Closed

Open

DTC Descriptors

This diagnostic procedure supports the following DTC:

DTC P0441 Evaporative Emission (EVAP) System Continuous Purge Flow

Conditions for Running the DTC

    • DTCs P0106, P0107, P0108, P112, P0113, P0117, P0118, P0122, P0123, P0131, P0132, P0133, P0134, P0135, P0137, P0138, P0140, P0141, P0201, P0202, P0203, P0204, P0300, P0402, P0404, P0405, P0406, P0443, P0452, P0453, P0462, P0463, P0488, P0502, P0506, P0507, P2195, and P2196 are not set.
    • The ignition 1 voltage is between 11-16 volts.
    • The barometric pressure (BARO) is more than 72 kPa.
    •  The engine run time is more than 1 second and less than 120 seconds.
    • The engine coolant temperature (ECT) and the intake air temperature (IAT) at start-up are between -5 and +40°C (+23 and +140°F).
    • The start-up IAT minus the start-up ECT is within 12°C (22°F).
    • The start-up ECT minus start-up IAT is within 50°C (90°F).
    • The start-up IAT minus IAT are within 3°C (5°F).
    • 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.

Diagnostic Aids

The EVAP system tests run when engine is first started and meets The Conditions for Running the DTC. An intermittent condition could be caused by an improperly installed or damaged EVAP canister purge solenoid valve , or by a temporary blockage or restriction in the EVAP canister purge solenoid valve.

Step

Action

Values

Yes

No

Schematic Reference: Evaporative Emissions Hose Routing Diagram

1

Did you perform the Diagnostic System Check - Engine Controls?

--

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2

  1. Disconnect the EVAP purge solenoid valve electrical harness connector.
  2. Start the engine.
  3. Command the vent solenoid closed with a scan tool.
  4. Increase the engine idle to 1,200-1,500 RPM.
  5. 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

--

5

Replace the fuel tank pressure (FTP) sensor. Refer to Fuel Tank Pressure Sensor Replacement .

Did you complete the replacement?

--

Go to Step 6

--

6

  1. Disconnect the EVAP purge solenoid valve electrical harness connector.
  2. Start the engine.
  3. Command the vent solenoid closed with a scan tool.
  4. Increase the engine idle to 1,200-1,500 RPM.
  5. 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 7

Go to Step 2

7

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List

System OK