SMU for Powertrain and Engine Service Manuals Regarding Evaporative Emission Flowcharts and EVAP Pressure/Purge Diagnostic Cart Test Procedure #02-T-02 - (Sep 30, 2003)

1998 - 2002 Saturn S-Series vehicles

2000 - 2002 Saturn L-Series vehicles

2002 Saturn VUE vehicles

Purpose

The purpose of this bulletin is to update P0440, P0442, and P0455 evaporative emission flowcharts and EVAP Pressure/Purge Diagnostic Cart Test Procedure to reflect the use of new special tool J41750-A, Evaporative Emissions System Tester, which replaces J41750. Update the flowcharts and EVAP Pressure/Purge Diagnostic Cart Test Procedure in the following service manuals:

• All 1998/1999 Powertrain and 2000 - 2002 S-Series Engine Service Manuals.
• All 2000, 2001, and 2002 L-Series (L61) and (L81) Engine Service Manuals.
• All 2002 VUE Powertrain Electrical Diagnostic Service Manuals.

Please obtain all service manuals indicated above at your location and make the necessary updates to each manual. Replace the service manual pages indicated in the tables with a copy of new DTC flowcharts or procedure page in this bulletin as indicated below.

1. Using a marker or pen, cross out the items on the service manual (SM) pages indicated in the tables listed in this bulletin.
2. On each item crossed out, write the following:
"Refer to Technical Information Bulletin 01-T-02"
3. Make copies of appropriate bulletin page and insert into service manuals as indicated in the tables.

Service manual update page for DTC P0440 flowchart. Refer to Technical Information Bulletin 01-T-02, January 2002.

Service manual update page for DTC P0442 flowchart. Refer to Technical Information Bulletin 01-T-02, January 2002.

Service manual update page for DTC P0440 and P0455 flowchart. Refer to Technical Information Bulletin 01-T-02, January 2002.

Service manual update page for DTC P0442 flowchart. Refer to Technical Information Bulletin 01-T-02, January 2002.

Service manual update for EVAP Pressure/Purge Diagnostic Cart Test Procedure. Refer to Technical Information Bulletin 01-T-02, December 2001.

EVAPORATIVE EMISSIONS SYSTEM LEAK TEST

Diagnostic Process

ENSURE THAT VEHICLE UNDERBODY TEMPERATURE IS SIMILAR TO AMBIENT TEMPERATURE, AND ALLOW SURROUNDING AIR TO STABILIZE BEFORE STARTING DIAGNOSTIC PROCEDURE.

1. Ignition ON, engine OFF. Seal EVAP system using scan tool.
2. Connect Evaporative Emission System Tester (EEST) red battery clip to positive (+) battery terminal. Connect black battery clip to chassis ground.
3. Connect EEST's nitrogen/smoke hose onto EVAP service port. Refer to appropriate service manual for EVAP service port location.
4. Turn NITROGEN/SMOKE valve to SMOKE.
5. Inject smoke into EVAP system.
6. Verify smoke has filled EVAP system by removing gas cap. Smoke is visible leaving fuel fill pipe when system is full. Reinstall gas cap. Introduce smoke for 60 additional seconds.
7. Use a high intensity white light (J41413-SPT) to inspect entire EVAP system for exiting smoke. Induce smoke at 15 second intervals, as needed, until leak source is identified. If leak source is not identified, go to Verification Process.

Verification Process

FLOWMETER TEST

1. Turn NITROGEN/SMOKE valve to NITROGEN.
2. Disconnect nitrogen/smoke hose from EVAP service port.
3. Connect hose to correct test orifice on bottom-front of EEST. Refer to the above chart:
4. Use remote switch to activate EEST.
5. Align red flag on flowmeter with floating indicator. Use remote switch to deactivate EEST.
6. Remove hose from test orifice; reinstall onto EVAP service port.
7. Ignition ON, engine OFF. Seal EVAP system using a scan tool.
8. Activate nitrogen flow and fill the system. Watch floating indicator until it stabilizes and stops dropping.

Important

Larger volume fuel tanks, and/or those with lower fuel levels, may require several minutes for floating indicator to stabilize.

9. Compare flowmeter's stable floating indicator position to red flag. If indicator floats:
• ABOVE red flag - UNACCEPTABLE (FAIL-return to service information).
• BELOW red flag - ACCEPTABLE (PASS-test completed).

SERVICE BAY TEST

Disconnect nitrogen/smoke hose from vehicle. Install service port cap. Perform EVAP Service Bay Test using a scan tool.

• If vehicle passes Service Bay Test, testing is complete.
• If vehicle does not pass, return to service information.

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer".  They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle.  Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely.  If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition.  See your GM dealer for information on whether your vehicle may benefit from the information.

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