GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2003 🢒 S10 Pickup - 2WD 🢒 DTC 🢒 DTC P0440

System Description

The control module tests the evaporative emission (EVAP) system for a large leak. The control module monitors the fuel tank pressure (FTP) sensor signal to determine the EVAP system vacuum level. When the conditions for running are met, the control module commands the EVAP canister purge valve OPEN and the EVAP vent valve CLOSED . This allows engine vacuum to enter the EVAP system. At a calibrated time, or vacuum level, the control module commands the EVAP canister purge valve closed, sealing the system, and monitors the FTP sensor input in order to determine the EVAP system vacuum level. If the system is unable to achieve the calibrated vacuum level, or the vacuum level decreases too rapidly, 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 valves.

Control Module Command

EVAP Canister Purge Valve

EVAP Canister Vent Valve

ON

Open

Closed

OFF

Closed

Open

Conditions for Running the DTC
    • DTCs P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0122, P0123, P0125, P0452, P0453 are not set.
    • The engine is running.
    • The ignition voltage is between 10-18 volts.
    • The barometric pressure (BARO) is more than 75 kPa.
    • The fuel level is between 15-85 percent.
    • The engine coolant temperature (ECT) is between 4-30°C (39-86°F).
    • The intake air temperature (IAT) is between 4-30°C (39-86°F).
    • The start-up ECT and IAT are within 9°C (16°F) of each other.
    • The vehicle speed sensor (VSS) is less than 121 km/h (75 mph).

Conditions For Setting the DTC

The EVAP system is not able to achieve or maintain vacuum during the diagnostic test.

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
    • To help locate intermittent leaks, use the J 41413-200 Evaporative Emissions System Tester (EEST) to introduce smoke into the EVAP system. Move all EVAP components while observing smoke with the J 41413-SPT High Intensity White Light.
    • A temporary blockage in the EVAP purge solenoid, purge pipe or EVAP canister could cause an intermittent condition. Inspect and repair any restriction in the EVAP system.
    • To improve the visibility of the smoke exiting the EVAP system, observe the suspected leak area from different angles with theJ 41413-SPT .
    • Reviewing the Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.
    • For intermittent conditions refer to Intermittent Conditions .

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This test verifies that the EVAP purge solenoid is electrically functional.

    2.

  2. This test verifies that the EVAP vent solenoid is electrically functional.

    3.

  3. Introducing smoke in 15 second intervals may allow smaller leak areas to be more noticeable. When the system is less pressurized, the smoke will sometimes escape in a more condensed manner.

  4. This test verifies that the fuel tank pressure (FTP) sensor is accurate. An FTP sensor that does not correctly respond to vacuum, or pressure may cause this DTC to set.

Step

Action

Values

Yes

No

Schematic Reference: Engine Controls Schematics and Evaporative Emissions Hose Routing Diagram

Connector End View Reference: Powertrain Control Module Connector End Views or Engine Controls Connector End Views

1

Did you perform the Diagnostic System Check-Engine Controls?

--

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2
  1. Inspect the EVAP system for the following conditions:
    2. • A loose, missing, or damaged service port schrader valve
    • A loose, incorrect, missing, or damaged fuel fill cap
    • A damaged EVAP purge solenoid
  2. Raise the vehicle on a hoist. Refer to Lifting and Jacking the Vehicle in General Information.
  3. Inspect the EVAP system for the following conditions:
    4. • Any disconnected, improperly routed, kinked, or damaged EVAP pipes and hoses
    • A damaged EVAP vent solenoid or EVAP canister

Did you find and correct the condition?

--

Go to Step 34

Go to Step 3

3

  1. Clear the DTCs with a scan tool.
  2. Command the EVAP purge solenoid to 50 percent and back to 0 percent with a scan tool.

Do you hear or feel a clicking from the EVAP purge solenoid when it is commanded to 50 percent?

--

Go to Step 4

Go to Step 5

4

Command the EVAP vent solenoid ON and OFF with the scan tool.

Do you hear or feel a click as the EVAP vent solenoid is commanded ON and OFF?

--

Go to Step 9

Go to Step 7

5
  1. Disconnect the EVAP purge solenoid.
  2. Turn ON the ignition, with the engine OFF.
  3. Connect a test lamp between the ignition 1 voltage circuit of the EVAP purge solenoid and a known good ground. Refer to Troubleshooting with a Test Lamp in Wiring Systems.

Does the test lamp illuminate?

--

Go to Step 6

Go to Step 25

6
  1. Connect a test lamp between the ignition 1 voltage circuit of the EVAP purge solenoid and the control circuit of the EVAP purge solenoid. Refer to Circuit Testing in Wiring Systems.
  2. Command the EVAP purge solenoid to 50 percent and then to 0 percent with a scan tool.

Does the test lamp illuminate or pulsate when the EVAP purge solenoid is commanded to 50 percent and turn OFF when the EVAP purge solenoid is commanded to 0 percent?

--

Go to Step 20

Go to Step 18

7
  1. Turn ON the ignition, with the engine OFF.
  2. Disconnect the EVAP vent solenoid.
  3. Connect a test lamp between the ignition 1 voltage circuit of the EVAP vent solenoid and a known good ground. Refer to Troubleshooting with a Test Lamp in Wiring Systems.

Does the test lamp illuminate?

--

Go to Step 8

Go to Step 26

8
  1. Connect a test lamp between the ignition 1 voltage circuit of the EVAP vent solenoid and the control circuit of the EVAP vent solenoid. Refer to Troubleshooting with a Test Lamp in Wiring Systems.
  2. Command the EVAP vent solenoid ON, with a scan tool.

Does the test lamp illuminate?

--

Go to Step 21

Go to Step 19

9

Important: Ensure that the vehicle underbody temperature is similar to the ambient temperature and allow the surrounding air to stabilize before starting the diagnostic procedure. System flow will be less with higher temperatures.

  1. Turn OFF the ignition.
  2. Connect the J 41413-200 Evaporative Emissions System Tester (EEST) power supply clips to a known good 12-volt source.
  3. Install the J 41415-40 Fuel Tank Cap Adapter to the fuel fill pipe.
  4. Connect the fuel fill cap to the J 41415-40 .
  5. Connect the J 41413-200 nitrogen/smoke supply hose to the J 41415-40 .
  6. Turn ON the ignition, with the engine OFF
  7. Command the EVAP vent solenoid closed with a scan tool.
  8. Turn the nitrogen/smoke valve on the J 41413-200 control panel to SMOKE.
  9. Use the remote switch to introduce smoke into the EVAP system.
  10. Use the J 41413-VLV EVAP Service Port Vent Fitting to open the EVAP service port.
  11. Remove the J 41413-VLV once smoke is observed.
  12. Continue to introduce smoke into the EVAP system for an additional 60 seconds.
  13. Inspect the entire EVAP system for exiting smoke with the J 41413-SPT High Intensity White Light.
  14. Continue to introduce smoke at 15 second intervals until the leak source has been located.

Did you locate and repair a leak source?

--

Go to Step 34

Go to Step 10

10
  1. Disconnect the J 41415-40 from the fuel fill pipe.
  2. Install the fuel fill cap to the fuel fill pipe.
  3. Connect the J 41413-200 nitrogen/smoke supply hose to the EVAP service port.
  4. Use the remote switch to introduce smoke into the EVAP system.
  5. Inspect the entire EVAP system for exiting smoke with the J 41413-SPT .
  6. Continue to introduce smoke at 15 second intervals until the leak source has been located.

Did you locate and repair a leak source?

--

Go to Step 34

Go to Step 11

11

  1. Use the remote switch to stop introducing smoke.
  2. Install the J 41415-40 to the fuel fill pipe.
  3. Connect the J 41413-200 nitrogen/smoke supply hose to the J 41415-40 .
  4. Connect the vehicle fuel fill cap to the J 41415-40 .
  5. Command the EVAP vent solenoid open with a scan tool.
  6. Compare the Fuel Tank Pressure Sensor parameter with a scan tool, to the J 41413-200 pressure/vacuum gage.

Is the scan tool Fuel Tank Pressure Sensor parameter within the specified value of the J 41413-200 pressure/vacuum gage?

1 in H2O

Go to Step 12

Go to Step 22

12
  1. Seal the EVAP system using the EVAP Purge/Seal function with a scan tool.
  2. Turn the nitrogen/smoke valve on theJ 41413-200 control panel to NITROGEN.
  3. Use the J 41413-200 to pressurize the EVAP system to the first specified value.

Is the Fuel Tank Pressure Sensor parameter more than the second specified value?

10 in H2O

5 in H2O

Go to Step 13

Go to Step 22

13
  1. Use the remote switch to stop introducing nitrogen into the EVAP system.
  2. Increase the EVAP purge solenoid to 100 percent.

Is the Fuel Tank Pressure Sensor parameter less than the specified value?

1 in H2O

Go to Diagnostic Aids

Go to Step 14

14

Disconnect the EVAP purge vacuum source from the EVAP purge solenoid.

Is the Fuel Tank Pressure Sensor parameter less than the specified value?

1 in H2O

Go to Step 24

Go to Step 15

15

Disconnect the EVAP purge pipe from the EVAP purge solenoid.

Is the Fuel Tank Pressure Sensor parameter less than the specified value?

1 in H2O

Go to Step 29

Go to Step 16

16

Disconnect the EVAP purge pipe at the EVAP canister.

Is the Fuel Tank Pressure Sensor parameter less than the specified value?

1 in H2O

Go to Step 27

Go to Step 17

17

Disconnect the EVAP vapor pipe at the EVAP canister.

Is the Fuel Tank Pressure Sensor parameter less than the specified value?

1 in H2O

Go to Step 31

Go to Step 28

18

Test the control circuit of the EVAP purge solenoid for an open or for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 34

Go to Step 23

19

Test the control circuit of the EVAP vent solenoid for an open or for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 34

Go to Step 23

20

Test for an intermittent and for a poor connection at the EVAP canister purge solenoid. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 34

Go to Step 29

21

Test for an intermittent and for a poor connection at the EVAP vent solenoid. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 34

Go to Step 30

22

Test for an intermittent and for a poor connection at the FTP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 34

Go to Step 32

23

Test for an intermittent and for a poor connection at the control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 34

Go to Step 33

24

Repair the pinched or obstructed EVAP purge solenoid vacuum source.

Did you complete the repair?

--

Go to Step 34

--

25
  1. Repair the open or short to ground in the ignition 1 voltage circuit of the EVAP purge solenoid. Refer to Wiring Repairs in Wiring Systems.
  2. Replace the fuse as necessary.

Did you complete the repair?

--

Go to Step 34

--

26

Repair the open or short to ground in the ignition 1 voltage circuit of the EVAP vent solenoid. Refer to Wiring Repairs in Wiring Systems. Replace the fuse as necessary.

Did you complete the repair?

--

Go to Step 34

--

27

Repair the restriction in the EVAP purge pipe. Refer to Evaporative Emission System Cleaning .

Did you complete the repair?

--

Go to Step 34

--

28

Repair the restriction in the EVAP vapor pipe.

Did you complete the repair?

--

Go to Step 34

--

29

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

Did you complete the replacement?

--

Go to Step 34

--

30

Replace the EVAP vent solenoid. Refer to Evaporative Emission Canister Vent Solenoid Valve Replacement .

Did you complete the replacement?

--

Go to Step 34

--

31

Replace the EVAP canister. Refer to Evaporative Emission Canister Replacement .

Did you complete the replacement?

--

Go to Step 34

--

32

Replace the FTP sensor. Refer to Fuel Tank Pressure Sensor Replacement .

Did you complete the replacement?

--

Go to Step 34

--

33

Replace the control module. Refer to Powertrain Control Module Replacement .

Did you complete the replacement?

--

Go to Step 34

--

34

Important: Do not exceed the specified value in this step. Exceeding the specified value may produce incorrect test results.

  1. Connect the J 41413-200 to the fuel fill pipe.
  2. Turn the nitrogen/smoke valve to NITROGEN.
  3. Seal the EVAP system using the EVAP purge/seal function with a scan tool.
  4. Pressurize the EVAP system to the specified value.
  5. Observe the J 41413-200 pressure/vacuum gage for 5 minutes.

Does the J 41413-200 pressure/vacuum gage remain constant?

5 in H2O

Go to Step 35

Go to Step 2

35

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