Back To Blog Academy

Ford Fusion Replace Evaporative Emissions (EVAP) Canister Vent Valve To Fix DTC P0456

By R&D
Published on March 12th, 2024

As an Amazon associate, we earn from qualifying purchases.

Purpose

To guide you on how to check and replace the Evaporative Emission (EVAP) Canister Vent Valve Solenoid.

Introduction

The Evaporative Emission Control (EVAP) System prevents gasoline vapors in the fuel system and fuel tank from escaping into the atmosphere where they could form unhealthful photochemical smog. Once gasoline vapors are collected in the charcoal canister, the Engine Control Module (ECM) controls the Purge Control Solenoid Valve (PCSV) to let any collected vapors from the canister back into the engine combustion chamber.

The ECM controls and monitors the operation of the EVAP System. Any leak in the EVAP system makes the ECM set the Diagnostic Trouble Code (DTC) P0456.

Ford Fusion.png__PID:72059816-3392-4122-bcb1-c16512b92c16

Innova Scan Tool indicates DTC P0456

In the 2016 Ford Fusion L4 2.0L, the ECM will set this DTC when it monitors the EVAP operation and detects any excessive fuel tank vacuum when the engine is running, but not at idling. The possible causes of this code are listed below:

- EVAP purge valve open - stuck

- EVAP system tubes blocked

- Capless fuel tank filler pipe damaged preventing vacuum relief

- Fuel vapor elbow contaminated on the EVAP canister

- EVAP canister restricted

- EVAP canister vent valve stuck

- EVAP canister vent valve filter plugged

- Voltage Reference (VREF) circuit opened

- Fuel Tank Pressure sensor damaged

Ford Fusion 2.jpg__PID:a5085262-3c9a-435c-8ca1-8d5746f6d2a9
Table header 0Step

Time required (hour)
Sections
Cautions

12
0.7
4
1
ModelPart numberPart name
2016 Ford Fusion 2.0L
CU5A9G886AA
CU5Z9F945A

EVAP purge control valve
EVAP canister vent valve

(This image is for illustrative purposes only and may not match the actual part number)

Diagnostic Procedures:

Initial Inspection

During your initial inspection, check for obvious mechanical signs such as torn inlet boots, missing or broken vacuum tees, and/or cracked, broken, or disconnected wire harnesses. Make sure all harness connectors are properly placed in the connectors and holders. This will prevent potential open or short-circuit issues. Also, check the connector for corrosion, frayed wiring, and damaged terminals.

Always check for cracked or broken fuel hoses, vacuum lines and pipes and fuel cap before attempting to diagnose EVAP leaks. This fault may be caused by water entering the canister close valve causing damage to the filter, valve, and charcoal canister. The first check should be a vacuum check of the valve to see if stuck open or frozen shut.

Refer to the Vehicle Emissions Warranty Manual to confirm time and mileage coverage for emissions-related fault(s). For additional information, refer to the Service Manual or applicable Technical Service Bulletin (TSB).

Diagnostic Procedure

Step 1: Turn vehicle ignition to the ON position. Use a Scan Tool to access the Active Test/Canister Vent Valve to activate the valve. Clicking noise should be heard when operating the valve.

If a clicking noise is heard, check the rubber tube for clogging and clean if necessary. Perform Repair Validation.

If a clicking noise is not heard, go to step 2.

Step 2: Turn vehicle ignition to the OFF position. Disconnect the EVAP canister vent valve connector. Turn vehicle ignition to the Key ON Engine OFF (KOEO) position. Using a Digital Multimeter (DMM), measure the voltage between Pin 2 (Green) and the ground. Voltage should be the Battery Voltage.

If the voltage is within specification, check the wiring between Pin 1 (Green/Blue) and the Engine Control Module (ECM) for open or short circuits. Perform Repair Validation.

If the voltage is out of specification, check the wiring between the valve and the Battery Junction Box for open or short circuits. Perform Repair Validation.

If the same DTC is set, go to step 3.

Step 3: Turn vehicle ignition to the OFF position. Use a DMM to measure the resistance between Pin 1 (Green/Blue) and Pin 2 (Green). The value should be 12–80 Ohms.

If the resistance is within specification, go to Step 4.

If the resistance is out of specification, replace the EVAP canister vent valve. Perform Repair Validation.

Step 4: Remove the EVAP canister vent valve from the EVAP canister and reconnect the disconnected connectors. Turn Vehicle ignition ON. Use a Scan Tool to access the Active Test/Canister Vent Valve to activate the valve. The EVAP canister vent valve is normally open to airflow. When the vent is energized, no airflow should be detected.

If the air flows properly, perform Repair Validation. If the same DTC is set, go to step 1.

If the air does not flow properly, replace the EVAP canister vent valve. Perform Repair Validation.

Replace the EVAP canister vent valve

Removal

Step 1 – Lift the vehicle and ensure the transmission is in NEUTRAL.

Step 2 – Disconnect the negative battery cable.

Step 3 – Remove the EVAP canister.

Disconnect the EVAP canister vent valve solenoid connector and quick connect and perform the procedure again to the couplings.

Remove the nuts which hold the canister (35 in-lb (4Nm))

Step 4 – Remove the EVAP canister vent valve solenoid by rotating clockwise.

Install

To install, reverse all removal steps above.

Repair Validation

Step 1: Connect the Scan Tool. Clear DTC(s) and Freeze Frame (FF) information.

Step 2: Validate the repair by following the EVAP drive cycle requirements for the fault area.

Step 3: Check for pending or stored DTC(s).

Step 4: If other DTCs are set, follow the appropriate diagnostic procedure and repair as specified.

Back To Blog Academy

Have Questions?

Hop in the discussion board on our community site!
It's a place where we help each other answer questions. Like Reddit but for automotive lovers.

Visit Community