Possible Causes

DTCs P0441 and P0446 use two-trip detection logic. DTC is set if a leak is detected in EVAP system, or when malfunction exists with the EVAP Vacuum Switching Valve (VSV), vapor pressure sensor or pressure switching valve VSV. Possible causes are:

• Vapor pressure sensor circuit is open or shorted.
• Defective vapor pressure sensor.
• EVAP VSV circuit is open or shorted.
• Defective EVAP VSV.
• Pressure switching valve VSV circuit is open or shorted.
• Defective pressure switching valve VSV.
• Canister closed valve VSV circuit is open or shorted.
• Defective canister closed valve VSV.
• Damaged, disconnected or restricted vacuum hose(s) or tubes.
• Fuel tank cap is loose or improperly installed.
• Defective fuel tank cap.
• Damaged fuel inlet pipe or fuel tank.
• Defective charcoal canister.
• Defective overfill check valve.
• Defective ECM.