CHECK ENGINE LITE
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Intermediate
Joined: Feb 2003
Posts: 33
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From: SPOKANE WA
CHECK ENGINE LITE
MY CHECK ENGINE LITE COMES ON AND I HAVE CHECKED THE ONBOARD COMPUTER AND IN THE 10 PCNI POWER TRAIN CONTROL MODULE I GET A CODE OF P0440 H C, I CANNOT FIND THIS CODE ON MY CODE READOUT SHEETS. CAN SOMEONE HELP ME WITH THIS? ALSO, I CLEAR THE CODE THE LIGHT GOES OUT BUT AFTER DRIVING ABOUT 300 MILES IT COMES BACK ON DISPLAYING THE SAME CODE.
THANKS
DAVE
THANKS
DAVE
Race Director
Joined: Mar 2000
Posts: 17,602
Likes: 20
From: Palm City Florida
Re: CHECK ENGINE LITE (NIVLAG)
SOunds like you might be fueling with the motor running....
Here is a bulletin
Info - Evaporative Emissions DTC P0440, P0441, P0442, P0446 #00-06-04-011A - (10/04/2001)
Evaporative Emissions DTC P0440, P0441, P0442, P0446
1996-2002 Passenger Cars and Trucks
With Enhanced Evaporative Emissions Engines
Except 1998-1999 Chevrolet Prizm
This bulletin is being revised to add model years and diagnostic enhancements. Please discard Corporate Bulletin Number 00-06-04-011 (Section 6-Engine).
Enhanced Evaporative Emissions testing of 1996 and newer vehicles with enhanced evaporative emissions requires more stringent testing of the fuel system for evaporative emissions leaks. Vehicles with this system use an on-board diagnostic module (i.e. Powertrain Control Module (PCM) or Vehicle Control Module (VCM) as the controller. For the balance of this bulletin, we will refer to either of these components as a module.
Enhanced Evaporative Emission tests may be performed by the vehicle's module when specific conditions are met. These conditions are determined by the calibration within the module. These calibrations are vehicle platform and engine family specific.
When the key is turned to the start or run position, the module checks the output of various sensors on the vehicle to determine when and if the Evaporative Emissions tests should be run. Refer to Engine Controls sub-section of the appropriate Service Manual for specific DTC information.
Some of the most widely used parameters are listed below:
The Barometric Pressure (BARO) is greater than a specified kPa (psi).
The system voltage is between 10 and 18 volts.
The intake air temperature (IAT) is within specified temperature values.
The engine coolant temperature (ECT) is within specified temperature values.
The ECT and IAT are within specified temperatures of each other when the vehicle engine was started.
The fuel level sensor indicates the fuel level is greater than a specified % of empty and less than a specified % of full. (For a 76 L (20 gal) fuel tank, a fuel level of more than 11 L (3 gal) but less than 64 L (17 gal) or as specified in the calibration).
Some platforms such as the Alero and Grand Am, use a miles driven check as well.
For the ECT and IAT to be within the specified temperatures of each other at the time of engine start-up, the engine will have to be in the non-running condition for a long enough period of time for the engine coolant temperature to drop from its normal operating temperature down to roughly 30°C (90°F). This could take several hours.
When the control module determines that the above conditions are met, the module tests for a leak in the EVAP system by:
Electrically closing the vent valve in order to seal the system.
Electrically opening the purge valve which allows the running engine to draw a vacuum on the fuel tank.
The module then closes the purge valve, resealing the system.
The module then monitors the fuel tank pressure sensor and determines:
If vacuum was achieved.
If a leak is present, how large the leak is.
If vacuum was not achieved.
If one of the above tests fails, the module remembers that the system failed the test.
If the module sees a failure of the EVAP test for two consecutive tests, the module will set a trouble code for EVAP leak (DTCs P0440, P0442, or P0446).
Important
If the PCM is completing the EVAP diagnostic, filling of the fuel tank cannot be completed as the vent valve will be closed and the fuel dispenser nozzle will sense the pressure build-up and shut down. This is the expected result. No parts should be replaced as nothing is faulty. To keep from encountering this situation, it is imperative all customers and dealership personnel be advised NOT TO FILL THE FUEL TANK WITH THE ENGINE RUNNING. If the condition is encountered, turn the ignition to the OFF position for a minute. This will allow the PCM to go to sleep completely, thereby opening the vent valve.
Here comes the long version...
The PCM tests the EVAP system for the following conditions:
Large and small leaks
Excess vacuum
Purge flow during non-commanded conditions
Fuel level and fuel pressure sensor faults
EVAP purge and vent valve faults
The PCM monitors the fuel tank pressure sensor in order to determine the level of vacuum/pressure in the EVAP system. The PCM commands both the EVAP Purge Solenoid and the EVAP Vent Valve ON when the Conditions for Running the DTC are met in order to apply an engine vacuum to the EVAP system. The PCM commands the EVAP purge solenoid OFF once the system has reached a predetermined level of vacuum. This test verifies if a vacuum can be achieved in the EVAP system. Failure to develop a vacuum may be caused by a large leak or a restriction. This DTC sets after twice failing the above test.
Conditions for Running the DTC
DTCs P0107, P0108, P0112, P0113, P0117, P0118, P0125, P0420, P0430, P0500, P0502, P0503, P0562, P0563, P1120, P1220, P1221, and HO2S DTCs are not set.
The ignition voltage is between 10 volts and 18 volts.
The barometric pressure is greater than 73 kPa (10.5 psi).
The fuel level is between 12.5 percent and 87.5 percent of full capacity.
The engine coolant temperature is between 4°C (39°F) and 30°C (86°F).
The intake air temperature is between 4°C (39°F) and 30°C (86°F).
The start up engine coolant and intake air temperatures are within 9°C (16°F) of each other.
Conditions for Setting the DTC
The EVAP system cannot develop a vacuum greater than a predetermined value.
Important
This DTC does not report a first failed test. A first fail of this DTC will have a scan tool status as Not Run. Use the scan tool data display parameter of EVAP Test Result to determine if this DTC has failed or passed for this ignition cycle.
Action Taken When the DTC Sets
The PCM illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the Failure Records.
Conditions for Clearing the MIL/DTC
The PCM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
A last test failed, or current DTC, clears when the diagnostic runs and does not fail.
A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
Use a scan tool in order to clear the MIL and the DTC.
Diagnostic Aids
Important
Remove any debris from the PCM\TAC module connector surfaces before servicing the PCM\TAC module. Inspect the PCM\TAC module connector gaskets when diagnosing/replacing the modules. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion into the PCM\TAC modules.
For any test that requires probing the PCM or a component harness connector, use the Connector Test Adapter Kit J 35616-A . Using this kit prevents damage to the harness/component terminals. Refer to Using Connector Test Adapters in Wiring Systems.
An accurate indication of fuel level is required for the PCM to properly Pass or Fail this DTC. Always diagnose fuel level sensor DTC's before performing this diagnostic table. Always monitor for fuel level sensor DTCs stored as History.
The Service Bay Test may have to be performed in cold ambient air temperatures when the vehicle is running a winter grade fuel. The scan tool displays a message when the service bay test does not run.
Perform a physical inspection of the EVAP system. Inspect for the following conditions:
A loose, missing, defective, or incorrect fuel tank cap
Incorrectly routed or defective EVAP system vacuum and vapor lines
A malfunctioning or damaged vapor canister
Inspect for charcoal release from the vapor canister. Refer to the Evaporative Emission (EVAP) System Cleaning procedure.
The vacuum and pressure in the EVAP system is measured in inches of H2O (water). Most gauges measure vacuum in inches of Hg (mercury) and pressure in psi (pounds per square inch). The following table illustrates how the values compare:
in. H2O
in. Hg.
psi
1 in. H2O
0.07 in. Hg
0.0361 psi.
5 in. H2O
0.36 in. Hg
0.180 psi.
10 in. H2O
0.73 in. Hg
0.361 psi.
15 in. H2O
1.10 in. Hg
0.541 psi.
Conditions for Running the Service Bay Test
The battery voltage is between 10.5 and 18.0 volts.
The fuel level is between 15 percent and 85 percent of the full capacity.
The engine temperature is between 3.5°C (38°F) and 35°C (95°F).
A fuel tank pressure sensor that is stuck in range will not cause DTC P0452/P0453 to set, but will cause DTC P0440/P0442 to set.
An open fuel tank pressure sensor ground circuit could cause this DTC to set.
For an intermittent, refer to Symptoms .
Test Description
The numbers below refer to the step numbers on the Diagnostic Table.
The components in this system are difficult to access . Thoroughly inspect all areas of the EVAP system. A fuel tank cap that is loose or off can cause this DTC to set.
The Service Bay Test will not run if the fuel level sensor voltage is out of range. The fuel level sensor voltage should be between 0.7-2.5 volts for both sensors. An intermittent leak or restriction is indicated if the vehicle passes the Service Bay Test.
If the Service Bay Test can not be run, proceed to Step 5.
This step is testing for a Fuel Tank Pressure sensor that is stuck in range. A sensor that is stuck in range will not cause DTC P0452/P0453 to set, but will cause DTC P0440/P0442 to set.
A Fuel Tank Pressure sensor that does not correctly respond to pressure (or vacuum) causes this DTC to set.
The Fuel Tank Pressure sensor range is from 7.5 in. H2O of pressure to -17.5 in. H2O of pressure (vacuum).
In order to test the Fuel Tank Pressure sensor for vacuum response, command the EVAP Purge Solenoid Valve ON with the engine running and quickly SEAL the system. Leaving the EVAP Purge Solenoid Valve ON for a longer period of time allows a greater level of vacuum to develop.
This step verifies if the Fuel Tank Pressure sensor responds when a vacuum is applied to the sensor.
This step tests the EVAP Purge Solenoid Valve for a leak.
Remove necessary components to access EVAP components. Refer to the information supplied with the EVAP pressure/purge diagnostic cart on proper setup and adjustment procedures.
This step is testing for a leak in the EVAP chassis pipe that comes from the EVAP Purge Solenoid Valve.
This step is testing the EVAP Canister and EVAP vent valve for a leak.
With pressure applied it may be necessary to disconnect the EVAP lines at the components to verify that a line or component is not restricted. A restriction would prevent a vacuum (or the Step 10 test pressure) from forming in the fuel tank.
This step is testing the complete fuel tank assembly for a leak. Thoroughly inspect the top of the fuel tanks for a leak.
With pressure applied it may be necessary to disconnect the EVAP lines at the components to verify that a line or component is not restricted. A restriction would prevent a vacuum or pressure from forming in the fuel tank.
DTC P0440 and P0442 Step
Action
Values
Yes
No
1
Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?
--
Go to Step 2
Go to Powertrain On Board Diagnostic (OBD) System Check
2
Are any other EVAP system DTC's set?
--
Go to Applicable DTC
Go to Step 3
3
Inspect the EVAP system for the following conditions:
A loose, incorrect, defective or missing fuel tank cap.
Disconnected, improperly routed, kinked or damaged EVAP system purge lines.
A damaged EVAP system component.
A damaged Fuel Pressure Connection Valve or a loose, missing, or damaged dust cap. Refer to the test description for additional information.
Repair the EVAP system as necessary.
Did you find and repair the condition?
--
Go to Step 24
Go to Step 4
4
Important
Ensure that The Conditions for Running the Service Bay test are met before proceeding with this diagnostic. Refer to Diagnostic Aids.
Perform the EVAP system Service Bay Test using a scan tool.
Does the EVAP diagnostic pass the Service Bay Test?
--
Go to Diagnostic Aids
Go to Step 5
5
Turn ON the ignition leaving the engine OFF.
Remove the fuel tank cap.
Monitor the fuel tank pressure using a scan tool.
Is the Fuel Tank Pressure near the specified value?
0 in. Hg.
Go to Step 6
Go to Step 7
6
Important
The DTCs must be cleared from the PCM in order to use the output control function on the scan tool.
Clear the DTCs using a scan tool.
Install the fuel tank cap.
Start and idle the engine.
Command the EVAP Purge Solenoid Valve to 50% using a scan tool.
Monitor the fuel tank pressure using a scan tool.
Does the Fuel Tank Pressure change when the EVAP Purge Solenoid Valve is enabled?
--
Go to Step 8
Go to Step 7
7
Turn ON the ignition leaving the engine OFF.
Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
Remove the right side wheelhouse panel. Refer to Wheelhouse Panel Replacement in Body Rear End. Removing the wheelhouse panel allows access to the EVAP canister access panel.
Remove the EVAP canister access panel. Removing the EVAP canister access panel allows access to the EVAP canister, hoses, pipes, and the Fuel Tank Pressure Sensor.
Remove the Fuel Tank Pressure sensor from the top of the right tank. Refer to Fuel Tank Pressure Sensor Replacement .
Connect the hand held vacuum pump J 23738-A to the vacuum port of the Fuel Tank Pressure sensor.
Attempt to apply a vacuum up to the specified value using the hand vacuum pump J 23738-A .
Monitor the Fuel Tank Pressure sensor using a scan tool.
Does the Fuel Tank Pressure sensor parameter change as vacuum is applied?
10 in Hg
Go to Step 8
Go to Step 23
8
Turn OFF the ignition.
Remove the EVAP Purge line from the EVAP Purge Solenoid Valve.
Connect the hand held vacuum pump J 23738-A to the vacuum port of the EVAP Purge Solenoid Valve.
Attempt to apply a vacuum up to the specified value using the hand vacuum pump.
Can the value specified be obtained and held?
10 in Hg
Go to Step 9
Go to Step 19
9
Important
If an audible click cannot be heard while commanding the solenoid ON and DTC P0443 is not set, inspect the EVAP Purge Solenoid Valve and circuits for high resistance.
Connect a vacuum gauge to the EVAP Purge Solenoid Valve .
Start the engine.
Command the EVAP Purge Solenoid Valve to 50% using a scan tool.
Is the vacuum measured on the gauge the same or more than the specified value?
12 in Hg
Go to Step 11
Go to Step 10
10
Turn OFF the ignition.
Remove the vacuum source line from the EVAP Purge Solenoid Valve.
Connect a vacuum gauge to the vacuum source.
Start the engine.
Is the vacuum measured on the gauge the same or more than the specified value?
12 in Hg
Go to Step 19
Go to Step 18
11
Important
This step is to limit component removal. Access to EVAP components is difficult. Attempt to locate the leak using the Ultrasonic Leak Detector J 41416 . Place the Ultrasonic Leak Detector J 41416 as close to components as possible.
Reconnect all the EVAP components.
Connect the EVAP Pressure/Purge Diagnostic Station J 41413 to the EVAP system service port.
Remove the right side wheelhouse panel. Refer to Wheelhouse Panel Replacement in Body Rear End. Removing the wheelhouse panel allows access to the EVAP canister access panel.
Remove the EVAP canister access panel. Removing the EVAP canister access panel allows access to the EVAP canister, hoses, pipes, and the Fuel Tank Pressure Sensor.
Command the EVAP Vent Valve ON (closed) using a scan tool.
Continuously attempt to pressurize the EVAP system by leaving the EVAP pressure/purge diagnostic station control **** in the pressurize position.
Using the Ultrasonic Leak Detector J 41416 attempt to locate a leak.
If you find a condition repair as necessary.
Did you find and repair the condition?
--
Go to Step 24
Go to Step 12
12
Turn OFF the ignition.
Disconnect the EVAP station.
Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
Remove right side muffler assembly (automatic transmission only). Refer to Muffler Replacement in Engine Exhaust.
Remove the EVAP Vent valve (near the right fuel tank) from the mounting bracket and reposition to gain access to the chassis EVAP pipe (aluminum with plastic coating). This pipe is from the EVAP Purge Solenoid Valve and goes to the EVAP canister. Refer to Evaporative Emission (EVAP) Vent Valve Replacement .
Disconnect the chassis EVAP purge pipe (aluminum with plastic coating) at the EVAP canister nylon purge pipe. Refer to Quick Connect Fitting(s) Service (Plastic Collar) .
Connect the Vacuum Pump J 23738-A to the chassis EVAP Purge pipe (from the EVAP Purge Solenoid Valve ).
Using the Vacuum Pump J 23738-A attempt to apply a vacuum up to the specified value.
Can the specified value of vacuum be obtained and held?
5 in Hg
Go to Step 13
Go to Step 22
13
Remove the right side wheelhouse panel. Refer to Wheelhouse Panel Replacement in Body Rear End. Removing the wheelhouse panel allows access to the EVAP canister access panel.
Remove the EVAP canister access panel. Removing the EVAP canister access panel allows access to the EVAP canister, hoses, pipes, and the Fuel Tank Pressure Sensor.
Disconnect the fuel tank vapor line from the EVAP Canister.
Plug the EVAP canister port for the fuel tank vapor line.
Disconnect the EVAP purge line from the EVAP canister.
Connect the Vacuum Pump J 23738-A to the EVAP Purge port on the EVAP canister.
Turn ON the ignition.
Command the EVAP Vent Valve ON (closed) with a scan tool.
Using the Vacuum Pump J 23738-A attempt to apply a vacuum up to the specified value.
Can the specified value of vacuum be obtained and held?
5 in Hg
Go to Step 16
Go to Step 14
14
Leave the system connected as in Step 13.
Disconnect the vent line at the EVAP Vent Valve.
Plug the vent line.
Attempt to apply a vacuum up to the specified value using the Vacuum Pump J 23738-A .
Can the specified value of vacuum be obtained and held?
5 in. Hg.
Go to Step 20
Go to Step 15
15
Inspect the following components for damage or leaks:
The EVAP Vent line from the canister to the EVAP Vent Valve.
The EVAP Canister Purge Nylon pipe (pipe from canister to chassis EVAP Purge pipe)
Missing/damaged O-ring seals.
If you find a condition repair as necessary.
Did you find and correct the condition?
--
Go to Step 24
Go to Step 21
16
Important
Do not overlook any items which could cause a DTC to set. Inspect for the following conditions while removing the fuel tanks:
Loose clamps
Kinked lines
Disconnected hoses/pipes/components
Damaged hoses/pipes/components
Damaged or missing O ring seals
Remove the left side fuel tank. Refer to Fuel Tank Replacement .
Remove the right side fuel tank. Refer to Fuel Tank Replacement .
Perform the Fuel Tank Leak test. Refer to Fuel Tank Leak Check .
Did you find and correct the condition?
--
Go to Step 24
Go to Step 17
17
Inspect all EVAP system components/pipes for restrictions. Refer to Evaporative Emission (EVAP) Control System Operation Description .
Repair condition as necessary.
Did you find and correct the condition?
--
Go to Step 24
Go to Step 2
18
Repair the vacuum source to the EVAP Purge Solenoid Valve.
Is the action complete?
--
Go to Step 24
--
19
Important
Inspect the EVAP Purge Solenoid Valve and the purge line for carbon contamination. Refer to Diagnostic Aids .
Replace the EVAP Purge Solenoid Valve. Refer to Evaporative Emission (EVAP) Canister Purge Solenoid Valve Replacement .
Is the action complete?
--
Go to Step 24
--
20
Replace the EVAP Vent Valve. Refer to Evaporative Emission (EVAP) Vent Valve Replacement .
Is the action complete?
--
Go to Step 24
--
21
Replace the EVAP Vapor Canister. Refer to Evaporative Emission (EVAP) Canister Replacement .
Is the action complete?
--
Go to Step 24
--
22
Replace the EVAP line from the EVAP Purge Solenoid Valve to the EVAP canister as necessary. Refer to Fuel Hose/Pipes Replacement - Chassis .
Is the action complete?
--
Go to Step 24
--
23
Replace the Fuel Tank Pressure sensor. Refer to Fuel Tank Pressure Sensor Replacement .
Is the action complete?
--
Go to Step 24
--
24
Important
Ensure that The Conditions for Running the Service Bay test are met before proceeding with this diagnostic. Refer to Diagnostic Aids.
Perform the EVAP system Service Bay Test using a scan tool.
Does the EVAP diagnostic pass the Service Bay Test?
--
Go to Step 25
Go to Step 5
25
Select the Capture Info option and the Review Info option using the scan tool.
Does the scan tool display any DTCs that you have not diagnosed?
--
Go to Applicable DTC
System OK
Here is a bulletin
Info - Evaporative Emissions DTC P0440, P0441, P0442, P0446 #00-06-04-011A - (10/04/2001)
Evaporative Emissions DTC P0440, P0441, P0442, P0446
1996-2002 Passenger Cars and Trucks
With Enhanced Evaporative Emissions Engines
Except 1998-1999 Chevrolet Prizm
This bulletin is being revised to add model years and diagnostic enhancements. Please discard Corporate Bulletin Number 00-06-04-011 (Section 6-Engine).
Enhanced Evaporative Emissions testing of 1996 and newer vehicles with enhanced evaporative emissions requires more stringent testing of the fuel system for evaporative emissions leaks. Vehicles with this system use an on-board diagnostic module (i.e. Powertrain Control Module (PCM) or Vehicle Control Module (VCM) as the controller. For the balance of this bulletin, we will refer to either of these components as a module.
Enhanced Evaporative Emission tests may be performed by the vehicle's module when specific conditions are met. These conditions are determined by the calibration within the module. These calibrations are vehicle platform and engine family specific.
When the key is turned to the start or run position, the module checks the output of various sensors on the vehicle to determine when and if the Evaporative Emissions tests should be run. Refer to Engine Controls sub-section of the appropriate Service Manual for specific DTC information.
Some of the most widely used parameters are listed below:
The Barometric Pressure (BARO) is greater than a specified kPa (psi).
The system voltage is between 10 and 18 volts.
The intake air temperature (IAT) is within specified temperature values.
The engine coolant temperature (ECT) is within specified temperature values.
The ECT and IAT are within specified temperatures of each other when the vehicle engine was started.
The fuel level sensor indicates the fuel level is greater than a specified % of empty and less than a specified % of full. (For a 76 L (20 gal) fuel tank, a fuel level of more than 11 L (3 gal) but less than 64 L (17 gal) or as specified in the calibration).
Some platforms such as the Alero and Grand Am, use a miles driven check as well.
For the ECT and IAT to be within the specified temperatures of each other at the time of engine start-up, the engine will have to be in the non-running condition for a long enough period of time for the engine coolant temperature to drop from its normal operating temperature down to roughly 30°C (90°F). This could take several hours.
When the control module determines that the above conditions are met, the module tests for a leak in the EVAP system by:
Electrically closing the vent valve in order to seal the system.
Electrically opening the purge valve which allows the running engine to draw a vacuum on the fuel tank.
The module then closes the purge valve, resealing the system.
The module then monitors the fuel tank pressure sensor and determines:
If vacuum was achieved.
If a leak is present, how large the leak is.
If vacuum was not achieved.
If one of the above tests fails, the module remembers that the system failed the test.
If the module sees a failure of the EVAP test for two consecutive tests, the module will set a trouble code for EVAP leak (DTCs P0440, P0442, or P0446).
Important
If the PCM is completing the EVAP diagnostic, filling of the fuel tank cannot be completed as the vent valve will be closed and the fuel dispenser nozzle will sense the pressure build-up and shut down. This is the expected result. No parts should be replaced as nothing is faulty. To keep from encountering this situation, it is imperative all customers and dealership personnel be advised NOT TO FILL THE FUEL TANK WITH THE ENGINE RUNNING. If the condition is encountered, turn the ignition to the OFF position for a minute. This will allow the PCM to go to sleep completely, thereby opening the vent valve.
Here comes the long version...
The PCM tests the EVAP system for the following conditions:
Large and small leaks
Excess vacuum
Purge flow during non-commanded conditions
Fuel level and fuel pressure sensor faults
EVAP purge and vent valve faults
The PCM monitors the fuel tank pressure sensor in order to determine the level of vacuum/pressure in the EVAP system. The PCM commands both the EVAP Purge Solenoid and the EVAP Vent Valve ON when the Conditions for Running the DTC are met in order to apply an engine vacuum to the EVAP system. The PCM commands the EVAP purge solenoid OFF once the system has reached a predetermined level of vacuum. This test verifies if a vacuum can be achieved in the EVAP system. Failure to develop a vacuum may be caused by a large leak or a restriction. This DTC sets after twice failing the above test.
Conditions for Running the DTC
DTCs P0107, P0108, P0112, P0113, P0117, P0118, P0125, P0420, P0430, P0500, P0502, P0503, P0562, P0563, P1120, P1220, P1221, and HO2S DTCs are not set.
The ignition voltage is between 10 volts and 18 volts.
The barometric pressure is greater than 73 kPa (10.5 psi).
The fuel level is between 12.5 percent and 87.5 percent of full capacity.
The engine coolant temperature is between 4°C (39°F) and 30°C (86°F).
The intake air temperature is between 4°C (39°F) and 30°C (86°F).
The start up engine coolant and intake air temperatures are within 9°C (16°F) of each other.
Conditions for Setting the DTC
The EVAP system cannot develop a vacuum greater than a predetermined value.
Important
This DTC does not report a first failed test. A first fail of this DTC will have a scan tool status as Not Run. Use the scan tool data display parameter of EVAP Test Result to determine if this DTC has failed or passed for this ignition cycle.
Action Taken When the DTC Sets
The PCM illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the Failure Records.
Conditions for Clearing the MIL/DTC
The PCM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
A last test failed, or current DTC, clears when the diagnostic runs and does not fail.
A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
Use a scan tool in order to clear the MIL and the DTC.
Diagnostic Aids
Important
Remove any debris from the PCM\TAC module connector surfaces before servicing the PCM\TAC module. Inspect the PCM\TAC module connector gaskets when diagnosing/replacing the modules. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion into the PCM\TAC modules.
For any test that requires probing the PCM or a component harness connector, use the Connector Test Adapter Kit J 35616-A . Using this kit prevents damage to the harness/component terminals. Refer to Using Connector Test Adapters in Wiring Systems.
An accurate indication of fuel level is required for the PCM to properly Pass or Fail this DTC. Always diagnose fuel level sensor DTC's before performing this diagnostic table. Always monitor for fuel level sensor DTCs stored as History.
The Service Bay Test may have to be performed in cold ambient air temperatures when the vehicle is running a winter grade fuel. The scan tool displays a message when the service bay test does not run.
Perform a physical inspection of the EVAP system. Inspect for the following conditions:
A loose, missing, defective, or incorrect fuel tank cap
Incorrectly routed or defective EVAP system vacuum and vapor lines
A malfunctioning or damaged vapor canister
Inspect for charcoal release from the vapor canister. Refer to the Evaporative Emission (EVAP) System Cleaning procedure.
The vacuum and pressure in the EVAP system is measured in inches of H2O (water). Most gauges measure vacuum in inches of Hg (mercury) and pressure in psi (pounds per square inch). The following table illustrates how the values compare:
in. H2O
in. Hg.
psi
1 in. H2O
0.07 in. Hg
0.0361 psi.
5 in. H2O
0.36 in. Hg
0.180 psi.
10 in. H2O
0.73 in. Hg
0.361 psi.
15 in. H2O
1.10 in. Hg
0.541 psi.
Conditions for Running the Service Bay Test
The battery voltage is between 10.5 and 18.0 volts.
The fuel level is between 15 percent and 85 percent of the full capacity.
The engine temperature is between 3.5°C (38°F) and 35°C (95°F).
A fuel tank pressure sensor that is stuck in range will not cause DTC P0452/P0453 to set, but will cause DTC P0440/P0442 to set.
An open fuel tank pressure sensor ground circuit could cause this DTC to set.
For an intermittent, refer to Symptoms .
Test Description
The numbers below refer to the step numbers on the Diagnostic Table.
The components in this system are difficult to access . Thoroughly inspect all areas of the EVAP system. A fuel tank cap that is loose or off can cause this DTC to set.
The Service Bay Test will not run if the fuel level sensor voltage is out of range. The fuel level sensor voltage should be between 0.7-2.5 volts for both sensors. An intermittent leak or restriction is indicated if the vehicle passes the Service Bay Test.
If the Service Bay Test can not be run, proceed to Step 5.
This step is testing for a Fuel Tank Pressure sensor that is stuck in range. A sensor that is stuck in range will not cause DTC P0452/P0453 to set, but will cause DTC P0440/P0442 to set.
A Fuel Tank Pressure sensor that does not correctly respond to pressure (or vacuum) causes this DTC to set.
The Fuel Tank Pressure sensor range is from 7.5 in. H2O of pressure to -17.5 in. H2O of pressure (vacuum).
In order to test the Fuel Tank Pressure sensor for vacuum response, command the EVAP Purge Solenoid Valve ON with the engine running and quickly SEAL the system. Leaving the EVAP Purge Solenoid Valve ON for a longer period of time allows a greater level of vacuum to develop.
This step verifies if the Fuel Tank Pressure sensor responds when a vacuum is applied to the sensor.
This step tests the EVAP Purge Solenoid Valve for a leak.
Remove necessary components to access EVAP components. Refer to the information supplied with the EVAP pressure/purge diagnostic cart on proper setup and adjustment procedures.
This step is testing for a leak in the EVAP chassis pipe that comes from the EVAP Purge Solenoid Valve.
This step is testing the EVAP Canister and EVAP vent valve for a leak.
With pressure applied it may be necessary to disconnect the EVAP lines at the components to verify that a line or component is not restricted. A restriction would prevent a vacuum (or the Step 10 test pressure) from forming in the fuel tank.
This step is testing the complete fuel tank assembly for a leak. Thoroughly inspect the top of the fuel tanks for a leak.
With pressure applied it may be necessary to disconnect the EVAP lines at the components to verify that a line or component is not restricted. A restriction would prevent a vacuum or pressure from forming in the fuel tank.
DTC P0440 and P0442 Step
Action
Values
Yes
No
1
Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?
--
Go to Step 2
Go to Powertrain On Board Diagnostic (OBD) System Check
2
Are any other EVAP system DTC's set?
--
Go to Applicable DTC
Go to Step 3
3
Inspect the EVAP system for the following conditions:
A loose, incorrect, defective or missing fuel tank cap.
Disconnected, improperly routed, kinked or damaged EVAP system purge lines.
A damaged EVAP system component.
A damaged Fuel Pressure Connection Valve or a loose, missing, or damaged dust cap. Refer to the test description for additional information.
Repair the EVAP system as necessary.
Did you find and repair the condition?
--
Go to Step 24
Go to Step 4
4
Important
Ensure that The Conditions for Running the Service Bay test are met before proceeding with this diagnostic. Refer to Diagnostic Aids.
Perform the EVAP system Service Bay Test using a scan tool.
Does the EVAP diagnostic pass the Service Bay Test?
--
Go to Diagnostic Aids
Go to Step 5
5
Turn ON the ignition leaving the engine OFF.
Remove the fuel tank cap.
Monitor the fuel tank pressure using a scan tool.
Is the Fuel Tank Pressure near the specified value?
0 in. Hg.
Go to Step 6
Go to Step 7
6
Important
The DTCs must be cleared from the PCM in order to use the output control function on the scan tool.
Clear the DTCs using a scan tool.
Install the fuel tank cap.
Start and idle the engine.
Command the EVAP Purge Solenoid Valve to 50% using a scan tool.
Monitor the fuel tank pressure using a scan tool.
Does the Fuel Tank Pressure change when the EVAP Purge Solenoid Valve is enabled?
--
Go to Step 8
Go to Step 7
7
Turn ON the ignition leaving the engine OFF.
Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
Remove the right side wheelhouse panel. Refer to Wheelhouse Panel Replacement in Body Rear End. Removing the wheelhouse panel allows access to the EVAP canister access panel.
Remove the EVAP canister access panel. Removing the EVAP canister access panel allows access to the EVAP canister, hoses, pipes, and the Fuel Tank Pressure Sensor.
Remove the Fuel Tank Pressure sensor from the top of the right tank. Refer to Fuel Tank Pressure Sensor Replacement .
Connect the hand held vacuum pump J 23738-A to the vacuum port of the Fuel Tank Pressure sensor.
Attempt to apply a vacuum up to the specified value using the hand vacuum pump J 23738-A .
Monitor the Fuel Tank Pressure sensor using a scan tool.
Does the Fuel Tank Pressure sensor parameter change as vacuum is applied?
10 in Hg
Go to Step 8
Go to Step 23
8
Turn OFF the ignition.
Remove the EVAP Purge line from the EVAP Purge Solenoid Valve.
Connect the hand held vacuum pump J 23738-A to the vacuum port of the EVAP Purge Solenoid Valve.
Attempt to apply a vacuum up to the specified value using the hand vacuum pump.
Can the value specified be obtained and held?
10 in Hg
Go to Step 9
Go to Step 19
9
Important
If an audible click cannot be heard while commanding the solenoid ON and DTC P0443 is not set, inspect the EVAP Purge Solenoid Valve and circuits for high resistance.
Connect a vacuum gauge to the EVAP Purge Solenoid Valve .
Start the engine.
Command the EVAP Purge Solenoid Valve to 50% using a scan tool.
Is the vacuum measured on the gauge the same or more than the specified value?
12 in Hg
Go to Step 11
Go to Step 10
10
Turn OFF the ignition.
Remove the vacuum source line from the EVAP Purge Solenoid Valve.
Connect a vacuum gauge to the vacuum source.
Start the engine.
Is the vacuum measured on the gauge the same or more than the specified value?
12 in Hg
Go to Step 19
Go to Step 18
11
Important
This step is to limit component removal. Access to EVAP components is difficult. Attempt to locate the leak using the Ultrasonic Leak Detector J 41416 . Place the Ultrasonic Leak Detector J 41416 as close to components as possible.
Reconnect all the EVAP components.
Connect the EVAP Pressure/Purge Diagnostic Station J 41413 to the EVAP system service port.
Remove the right side wheelhouse panel. Refer to Wheelhouse Panel Replacement in Body Rear End. Removing the wheelhouse panel allows access to the EVAP canister access panel.
Remove the EVAP canister access panel. Removing the EVAP canister access panel allows access to the EVAP canister, hoses, pipes, and the Fuel Tank Pressure Sensor.
Command the EVAP Vent Valve ON (closed) using a scan tool.
Continuously attempt to pressurize the EVAP system by leaving the EVAP pressure/purge diagnostic station control **** in the pressurize position.
Using the Ultrasonic Leak Detector J 41416 attempt to locate a leak.
If you find a condition repair as necessary.
Did you find and repair the condition?
--
Go to Step 24
Go to Step 12
12
Turn OFF the ignition.
Disconnect the EVAP station.
Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
Remove right side muffler assembly (automatic transmission only). Refer to Muffler Replacement in Engine Exhaust.
Remove the EVAP Vent valve (near the right fuel tank) from the mounting bracket and reposition to gain access to the chassis EVAP pipe (aluminum with plastic coating). This pipe is from the EVAP Purge Solenoid Valve and goes to the EVAP canister. Refer to Evaporative Emission (EVAP) Vent Valve Replacement .
Disconnect the chassis EVAP purge pipe (aluminum with plastic coating) at the EVAP canister nylon purge pipe. Refer to Quick Connect Fitting(s) Service (Plastic Collar) .
Connect the Vacuum Pump J 23738-A to the chassis EVAP Purge pipe (from the EVAP Purge Solenoid Valve ).
Using the Vacuum Pump J 23738-A attempt to apply a vacuum up to the specified value.
Can the specified value of vacuum be obtained and held?
5 in Hg
Go to Step 13
Go to Step 22
13
Remove the right side wheelhouse panel. Refer to Wheelhouse Panel Replacement in Body Rear End. Removing the wheelhouse panel allows access to the EVAP canister access panel.
Remove the EVAP canister access panel. Removing the EVAP canister access panel allows access to the EVAP canister, hoses, pipes, and the Fuel Tank Pressure Sensor.
Disconnect the fuel tank vapor line from the EVAP Canister.
Plug the EVAP canister port for the fuel tank vapor line.
Disconnect the EVAP purge line from the EVAP canister.
Connect the Vacuum Pump J 23738-A to the EVAP Purge port on the EVAP canister.
Turn ON the ignition.
Command the EVAP Vent Valve ON (closed) with a scan tool.
Using the Vacuum Pump J 23738-A attempt to apply a vacuum up to the specified value.
Can the specified value of vacuum be obtained and held?
5 in Hg
Go to Step 16
Go to Step 14
14
Leave the system connected as in Step 13.
Disconnect the vent line at the EVAP Vent Valve.
Plug the vent line.
Attempt to apply a vacuum up to the specified value using the Vacuum Pump J 23738-A .
Can the specified value of vacuum be obtained and held?
5 in. Hg.
Go to Step 20
Go to Step 15
15
Inspect the following components for damage or leaks:
The EVAP Vent line from the canister to the EVAP Vent Valve.
The EVAP Canister Purge Nylon pipe (pipe from canister to chassis EVAP Purge pipe)
Missing/damaged O-ring seals.
If you find a condition repair as necessary.
Did you find and correct the condition?
--
Go to Step 24
Go to Step 21
16
Important
Do not overlook any items which could cause a DTC to set. Inspect for the following conditions while removing the fuel tanks:
Loose clamps
Kinked lines
Disconnected hoses/pipes/components
Damaged hoses/pipes/components
Damaged or missing O ring seals
Remove the left side fuel tank. Refer to Fuel Tank Replacement .
Remove the right side fuel tank. Refer to Fuel Tank Replacement .
Perform the Fuel Tank Leak test. Refer to Fuel Tank Leak Check .
Did you find and correct the condition?
--
Go to Step 24
Go to Step 17
17
Inspect all EVAP system components/pipes for restrictions. Refer to Evaporative Emission (EVAP) Control System Operation Description .
Repair condition as necessary.
Did you find and correct the condition?
--
Go to Step 24
Go to Step 2
18
Repair the vacuum source to the EVAP Purge Solenoid Valve.
Is the action complete?
--
Go to Step 24
--
19
Important
Inspect the EVAP Purge Solenoid Valve and the purge line for carbon contamination. Refer to Diagnostic Aids .
Replace the EVAP Purge Solenoid Valve. Refer to Evaporative Emission (EVAP) Canister Purge Solenoid Valve Replacement .
Is the action complete?
--
Go to Step 24
--
20
Replace the EVAP Vent Valve. Refer to Evaporative Emission (EVAP) Vent Valve Replacement .
Is the action complete?
--
Go to Step 24
--
21
Replace the EVAP Vapor Canister. Refer to Evaporative Emission (EVAP) Canister Replacement .
Is the action complete?
--
Go to Step 24
--
22
Replace the EVAP line from the EVAP Purge Solenoid Valve to the EVAP canister as necessary. Refer to Fuel Hose/Pipes Replacement - Chassis .
Is the action complete?
--
Go to Step 24
--
23
Replace the Fuel Tank Pressure sensor. Refer to Fuel Tank Pressure Sensor Replacement .
Is the action complete?
--
Go to Step 24
--
24
Important
Ensure that The Conditions for Running the Service Bay test are met before proceeding with this diagnostic. Refer to Diagnostic Aids.
Perform the EVAP system Service Bay Test using a scan tool.
Does the EVAP diagnostic pass the Service Bay Test?
--
Go to Step 25
Go to Step 5
25
Select the Capture Info option and the Review Info option using the scan tool.
Does the scan tool display any DTCs that you have not diagnosed?
--
Go to Applicable DTC
System OK
