Tech Tip: Ford Vacuum Leakage Noise and MIL On with Lean Codes – UnderhoodService

Tech Tip: Ford Vacuum Leakage Noise and MIL On with Lean Codes

Some 2005 Taurus and Sable vehicles equipped with a 3.0L 2V and some 2003-2005 Lincoln LS vehicles equipped with a 3.0L 4V engine may exhibit a vacuum leakage noise or lean codes and/or malfunction indicator lamp (MIL) on.

Affected vehicles: 2005 Ford Taurus and Mercury Sable, and 2003-’05 Lincoln LS

Some 2005 Taurus and Sable vehicles equipped with a 3.0L 2V and some 2003-’05 Lincoln LS vehicles equipped with a 3.0L 4V engine may exhibit a vacuum leakage noise or lean codes and/or malfunction indicator lamp (MIL) on. The cause may be a leak at the O-ring on the intake manifold tuning (IMT) valve.

Follow the Service Procedure steps to correct the condition.

Service Procedure
Verify the concern by removing the IMT valve from the intake manifold and visually inspecting the O-ring condition. If the O-ring is flat or damaged, replace only the O-ring, not the actuator.

For Lincoln LS, refer to the 2005 Workshop Manual, Section 303-14, IMT valve.

For Taurus vehicles, the IMT valve is located on right front of upper intake manifold:
1. Remove the two retainers.

2. Disconnect the electrical connector.

3. Remove the IMT valve.

Note: Coat the IMT valve with clean engine oil before installing it in the intake manifold. If the IMT valve O-ring is not the cause, continue with normal diagnosis.

Courtesy Mitchell 1.

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