Test B: DTC P0455: Major Leak Or No Flow Detected Or DTC P1443: Very Small Or No Purge Flow Detected In System: LS
- Check For DTC P0455 Or P1443 - If DTC P0455 is present, go to next step. If DTC P0455 is not present, go to step 3.
- Check For Gross EVAP System Leaks
Check for presence of fuel cap, but do not tighten at this time. Ensure input port vacuum and EVAP return tube are connected to EVAP canister purge valve. Ensure canister vent is seated on EVAP canister. Check for damaged fuel tank or fuel filler pipe. Check EVAP hoses between intake manifold and the following points:- EVAP Canister Purge Valve
- EVAP Canister
- Fuel Vapor Vent Valve Assembly
- Fuel Vapor Control Valve Tube Assembly
If problem was found, repair or replace component as necessary and go to next step. If no problems were found, go to next step.
- Check For EVAP System Leaks
Disconnect and plug EVAP return tube at intake manifold. Perform evaporative emissions system leak test. See EVAPORATIVE EMISSIONS SYSTEM LEAK TEST . If system pressure stays above 1.99 kPa (8 In. H2O), go to next step. If system is not as specified, ensure fuel cap is installed properly and repair or replace components as necessary. Retest system. When system passes, perform EVAPORATIVE EMISSIONS REPAIR VERIFICATION DRIVE CYCLE. See DRIVE CYCLE PROCEDURES under ADDITIONAL SYSTEM FUNCTIONS. - Check For Blockage Between EVAP Canister Purge Valve & Canister Vent Solenoid
Turn ignition switch to ON position. Using scan tool, close canister vent solenoid. Select OUTPUT TEST MODE, FTP and VPID. Select ALL OFF mode. Press START button on scan tool to close canister vent solenoid. Using Evaporative Emissions System Leak Tester (134-00056) or equivalent, pressurize system to 3.48 kPa (14 In. H2O). Open canister vent solenoid. If pressure drops immediately, go to next step. If pressure does not drop immediately, go to TEST D . - Check For Blockage Between Fuel Filler Pipe & Fuel Vapor Control Valve Tube
Move EVAP tester from EVAP test port to fuel filler tube. Pressurize system to 6.47-6.97 kPa (26-28 In. H2O). If pressure drops immediately, go to next step. If pressure does not drop immediately, go to TEST D . - Check For Failed EVAP Canister Purge Valve Or Fuel Tank Pressure Sensor
If DTC P0455 and P1443 are present, replace EVAP canister purge valve. Perform evaporative emissions system leak test. See EVAPORATIVE EMISSIONS SYSTEM LEAK TEST . If system passes, perform EVAPORATIVE EMISSIONS REPAIR VERIFICATION DRIVE CYCLE. See DRIVE CYCLE PROCEDURES under ADDITIONAL SYSTEM FUNCTIONS. If DTC P0455 and P1443 are not present, install fuel tank. Perform evaporative emissions system leak test. See EVAPORATIVE EMISSIONS SYSTEM LEAK TEST . If system passes, perform EVAPORATIVE EMISSIONS REPAIR VERIFICATION DRIVE CYCLE. See DRIVE CYCLE PROCEDURES under ADDITIONAL SYSTEM FUNCTIONS.