Emissions - MIL ON/DTC P0446 (EVAP) Set
ENGINEEG007-05
Title:
M.I.L. "ON" DTC P0446 (ONLY)
Models:
'01 - '03 Sienna
February 16, 2005
Introduction
Some 2001 to 2003 model year Sienna vehicles may exhibit a M.I.L. "ON" with DTC P0446 (Evaporative Emission Control System Vent Control Malfunction). Debris inside the EVAP line restrictor orifice may cause this condition. This line is located between the tank valve on the charcoal canister and the fuel cut-off valves on the tank.
NOTE:
This TSB does not apply to vehicles with multiple EVAP system DTCs.
Applicable Vehicles
2001 - 2003 model year Sienna vehicles.
Parts Information
Warranty Information
Applicable Warranty*:
This repair is covered under the Toyota Federal Emissions Warranty. This warranty is in effect for 36 months or 36,000 miles, whichever occurs first, from the vehicle's in-service date.
* Warranty application is limited to correction of a problem based upon a customer's specific complaint.
Required SSTs
Repair Procedure
Diagnosis:
1. Confirm there are no vapor leaks present using both the EVAP Tester Kit and the Diagnostic Tester EVAP System Check Active Test.
2. Verify proper Purge, Bypass, and Canister Closed VSV operation.
3. If no other problems are found, inspect the EVAP line for restrictions using the following inspection procedure.
EVAP Line Obstruction/Restriction Inspection Procedure:
Refer to diagram below to identify the components affected by this condition.
1. Remove the charcoal canister protective cover.
2. Completely remove the rubber EVAP line (shown in red) from the system.
3. There is a silver metal restrictor inside the rubber EVAP line visible from the end furthest from the canister. Inspect for debris trapped in the restrictor orifice. (A flash light or shop light will be needed to look down the hose about 2 cm [0.79 in.].)
4. If debris is found, apply pressurized air to the opposite end of the rubber EVAP line to clear the restriction. It is helpful to wrap a rag around the end of the hose to capture any debris for confirmation. If the debris cannot be cleared, hose and restrictor replacement will be necessary (see Parts Information).
IMPORTANT:
DO NOT apply air pressure to any of the EVAP line components while they are still connected to the EVAP system or fuel tank!
5. Reinstall rubber EVAP line and confirm proper system operation.
6. If no debris is found, or if this procedure does not correct the condition, continue EVAP system diagnosis following the diagnostic procedure for DTC P0446 found on the Technical Information System (TIS), applicable model year Sienna Repair Manual:
Diagnostics: Engine: P0441, P0446 Evaporative Emission Control System VENT Control Malfunction.
7. Reinstall the charcoal canister protective cover. Torque 6 nuts to the following specifications.
Torque: 19.5 N.m (14 ft.lbf, 195 kgf.cm)