EVAP Vent Valve

This procedure covers the replacement of the EVAP vent valve on a 2007 Ram 3500 with the 5.9L Cummins diesel engine, which controls the venting of the evaporative emissions system.

Warnings

Tools required

Parts

• EVAP vent valve × 1 — Use OEM specification

Preparation

1. Park vehicle on level ground and engage parking brake.
2. Turn ignition off and remove key.
3. Allow engine to cool if recently driven.
4. Raise and support the rear of the vehicle on jack stands if additional clearance is needed (4WD models typically provide adequate clearance from the ground).

Procedure

1. 1

   Locate the EVAP vent valve
   Position yourself under the driver side of the vehicle near the rear. The EVAP vent valve is mounted to the frame rail forward of the fuel tank. It is a small cylindrical component with an electrical connector and two hose connections.
2. 2

   Disconnect the electrical connector
   Press the release tab on the electrical connector and pull it straight off the EVAP vent valve. If the connector is tight or corroded, gently wiggle it while pulling. Use a pick tool to carefully release the locking tab if necessary.
3. 3

   Disconnect the vent hose
   Locate the fresh air vent hose connected to the bottom or side of the valve (depending on valve orientation). Press the quick-connect release tabs or squeeze the plastic retaining clips and pull the hose straight off the valve. Some resistance is normal.
4. 4

   Disconnect the canister hose
   Disconnect the EVAP canister hose from the opposite port of the valve using the same method as the vent hose. This hose runs to the EVAP canister. Note the orientation of both hoses for proper reinstallation.
5. 5

   Remove the mounting fastener
   Using a 10mm socket and ratchet, remove the bolt or fastener securing the EVAP vent valve to the frame rail bracket. The valve may be held by a single bolt through a mounting tab or clipped into a bracket.
6. 6

   Remove the old EVAP vent valve
   Pull the EVAP vent valve out of its mounting bracket. If it's clipped in place, you may need to squeeze or release plastic tabs while pulling the valve free. Inspect the old valve for obvious damage or contamination.
7. 7

   Install the new EVAP vent valve
   Position the new EVAP vent valve into the mounting bracket in the same orientation as the old valve. Ensure any mounting tabs are properly aligned with the bracket. If the valve clips into place, push firmly until you hear or feel it click.
8. 8

   Install the mounting fastener
   Thread in the 10mm mounting bolt by hand to prevent cross-threading, then snug it down with the socket and ratchet. Tighten firmly but do not overtighten as the mounting tab may be plastic or thin metal.
9. 9

   Reconnect the EVAP hoses
   Push the canister hose and vent hose onto their respective ports on the new valve until you hear or feel them click into place. Verify both hoses are fully seated by attempting to pull them off with moderate force. They should not release without pressing the quick-connect tabs.
10. 10

    Reconnect the electrical connector
    Push the electrical connector onto the EVAP vent valve until it clicks into place. Ensure the locking tab is fully engaged. Gently tug on the connector to verify it is secure.

Reassembly

1. Lower the vehicle if it was raised on jack stands.
2. Ensure all hose connections are secure and properly routed away from sharp edges or heat sources.
3. Verify the electrical connector is fully seated and the locking tab is engaged.

Verification

• Start the engine and allow it to idle for several minutes.
• Check for any unusual sounds from the EVAP vent valve area.
• Using a scan tool, check for EVAP system diagnostic trouble codes. Clear any existing codes and perform a drive cycle.
• If available, use the scan tool to perform an EVAP system leak test or vent valve function test to confirm proper operation.
• Verify no check engine light illuminates after driving the vehicle through a complete drive cycle.

Related trouble codes on this vehicle

Codes that commonly send this job to the bay — tap one for symptoms, causes, and diagnostic steps.

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