This procedure covers removal and replacement of the crankshaft position sensor on the 3.6L V6 Pentastar engine in 2012-2018 Jeep Wrangler JK models.

Warnings

Tools required

Parts

• Crankshaft position sensor × 1 — Mopar 05150873AA or equivalent
• O-ring seal (if not included with sensor) × 1 — Use OEM specification

Preparation

1. Park vehicle on level ground and engage parking brake
2. Allow engine to cool completely if recently operated
3. Disconnect negative battery cable to prevent accidental starter engagement
4. Raise and support front of vehicle on jack stands if additional clearance is needed (recommended for easier access)
5. Remove driver side front wheel and inner fender liner for improved access (optional but helpful)

Procedure

1. 1

   Locate the crankshaft position sensor
   The sensor is mounted on the driver side of the engine block, just above where the engine meets the transmission bellhousing. It will have a single electrical connector and is held by one bolt. Use a flashlight to locate it from below or through the wheel well.
2. 2

   Disconnect the electrical connector
   Press the red tab or release mechanism on the electrical connector and pull it straight away from the sensor. You may need to wiggle it gently while pulling. Inspect the connector terminals for corrosion or damage.
3. 3

   Remove the sensor mounting bolt
   Using a 10mm socket, remove the single bolt securing the crankshaft position sensor to the engine block. The bolt may be tight due to thread locker compound. Keep this bolt as it will be reused unless damaged.
   Torque spec

   Mounting Bolts54 Nm (40 lb-ft)
4. 4

   Extract the sensor from the engine block
   Carefully pull the sensor straight out of its mounting bore in the engine block. It may require gentle twisting and pulling as the O-ring creates a seal. Do not pry against the sensor body or engine block. Avoid dropping the sensor into the bellhousing area.
5. 5

   Inspect the mounting bore and O-ring
   Check the sensor bore in the engine block for debris, metal shavings, or damage. Remove the O-ring from the old sensor (or from the bore if it stayed in place) and inspect for damage. Clean the bore opening with a clean shop towel. Do not allow debris to fall into the engine.
6. 6

   Prepare the new sensor
   Verify the new sensor matches the old unit exactly. Install the new O-ring onto the sensor body if not pre-installed. Lightly coat the O-ring with clean engine oil to aid installation and prevent tearing. Do not use excessive oil or grease that could contaminate the sensor tip.
7. 7

   Install the new crankshaft position sensor
   Carefully insert the new sensor straight into the mounting bore, ensuring the O-ring does not roll or get pinched. Push the sensor fully into place until it seats against the engine block. Align the mounting bolt hole.
8. 8

   Install and torque the mounting bolt
   Thread the mounting bolt by hand to ensure it is not cross-threaded. Tighten the bolt to 12.0 Nm (9 lb-ft) using a torque wrench. Do not overtighten as this can crack the sensor housing or damage the threads in the aluminum block.
   Torque spec

   Mounting Bolts54 Nm (40 lb-ft)
9. 9

   Reconnect the electrical connector
   Push the electrical connector firmly onto the sensor until you hear or feel it click into place. Gently tug on the connector to verify it is fully locked. Apply a small amount of dielectric grease to the connector if desired for corrosion protection.
10. 10

    Reinstall removed components
    If the inner fender liner and wheel were removed for access, reinstall them now. Ensure all fasteners are properly secured. Reconnect the negative battery cable.

Reassembly

1. Double-check that the electrical connector is fully seated and locked onto the sensor
2. Verify the sensor mounting bolt is torqued to specification
3. Ensure no tools or parts were left in the engine bay or wheel well area

Verification

• Turn the ignition key to the ON position (do not start) and verify the check engine light illuminates then goes out during bulb check
• Start the engine and verify it starts normally without extended cranking
• Check for any diagnostic trouble codes using an OBD-II scanner - codes P0335 or P0339 indicate crankshaft position sensor circuit problems
• Allow engine to idle and verify smooth operation with no misfires or stalling
• Inspect the sensor installation area for any oil leaks around the sensor O-ring
• Test drive the vehicle to confirm normal operation and that no warning lights appear

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