Manifold Absolute Pressure Sensor

This procedure covers the removal and replacement of the Manifold Absolute Pressure (MAP) sensor on the 3.5L EcoBoost engine, which monitors intake manifold pressure for engine management.

Warnings

Tools required

Parts

• Manifold Absolute Pressure (MAP) Sensor × 1 — Motorcraft CM5352 or equivalent

Preparation

1. Ensure engine is cool to the touch
2. Open the hood and secure it in the upright position
3. Disconnect the negative battery cable and wait 2 minutes for airbag system to discharge
4. Locate the MAP sensor on the intake manifold (passenger side, near firewall on the charge air cooler outlet pipe)

Procedure

1. 1

   Access the MAP sensor
   The MAP sensor is mounted on the charge air cooler outlet pipe between the turbochargers and throttle body. Clear any engine covers or hoses that may obstruct access. On some configurations, you may need to move aside the engine appearance cover.
2. 2

   Disconnect electrical connector
   Locate the electrical connector on the MAP sensor. Press the locking tab on the connector and pull straight away from the sensor. If the connector is stubborn, gently wiggle it while pulling. Inspect the connector terminals for corrosion or damage.
3. 3

   Remove MAP sensor mounting screws
   Using a 10mm socket or wrench, carefully remove the two screws securing the MAP sensor to the intake pipe. Support the sensor with one hand while removing the second screw to prevent it from falling. Keep track of the screws as they are small.
   Torque spec

   MAP Sensor Screws3 Nm (2 lb-ft)
4. 4

   Remove MAP sensor from manifold
   Gently pull the MAP sensor straight out from the intake pipe. The sensor has an O-ring seal that may cause slight resistance. If the O-ring remains in the bore, carefully extract it with a pick or small screwdriver. Inspect the O-ring for damage or deterioration.
5. 5

   Clean mounting surface
   Clean the MAP sensor mounting bore on the intake pipe with electrical contact cleaner. Remove any debris, dirt, or old O-ring material. Ensure the bore is completely clean and dry before installation. Inspect the bore for cracks or damage.
6. 6

   Prepare new MAP sensor
   Remove the new MAP sensor from packaging. Verify it matches the old sensor in appearance and connector type. Check that a new O-ring is installed on the sensor. Apply a light coat of dielectric grease to the O-ring to aid installation and provide moisture protection.
7. 7

   Install new MAP sensor
   Carefully insert the new MAP sensor into the mounting bore on the intake pipe. Ensure the sensor is properly oriented with the electrical connector facing the correct direction for easy connection. Push the sensor in firmly until it seats completely against the mounting surface. The O-ring should compress evenly.
   Torque spec

   MAP Sensor Screws3 Nm (2 lb-ft)
8. 8

   Torque MAP sensor screws
   Install the two MAP sensor mounting screws and hand-tighten them. Using a torque wrench, tighten the screws to 3.0 Nm (2.0 lb-ft) in a cross pattern. Do not overtighten as this can crack the sensor housing or strip the threads in the aluminum intake pipe.
   Torque spec

   MAP Sensor Screws3 Nm (2 lb-ft)
9. 9

   Reconnect electrical connector
   Apply a small amount of dielectric grease to the inside of the electrical connector if desired. Align the connector with the MAP sensor terminals and push firmly until you hear and feel a click. Gently tug on the connector to verify it is fully locked in place.
10. 10

    Restore battery connection
    Reconnect the negative battery cable and tighten securely. The PCM may need to relearn idle and fuel trim parameters after sensor replacement.

Reassembly

1. Reinstall any engine covers or components that were removed for access
2. Ensure all tools and parts are removed from the engine compartment
3. Double-check that the MAP sensor electrical connector is fully seated and locked

Verification

• Start the engine and verify it runs smoothly without rough idle or hesitation
• Check for diagnostic trouble codes using an OBD-II scanner; clear any codes related to the MAP sensor replacement
• Verify there are no vacuum leaks around the MAP sensor mounting area
• Perform a test drive and confirm normal engine performance and boost pressure under acceleration
• Monitor for any new check engine lights or performance issues over the next few drive cycles

Related trouble codes on this vehicle

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

Chasing one of these codes and not sure which part is guilty? Ask a master mechanic about YOUR car →

More procedures for this vehicle