Crankshaft Position Sensor

Remove and replace the crankshaft position sensor on a 2008 Dodge Viper with 8.4L V10 engine, located on the transmission bellhousing.

Warnings

Tools required

Parts

• Crankshaft position sensor × 1 — Mopar 05080454AA or equivalent

Preparation

1. Park vehicle on level ground and allow engine to cool completely (minimum 2 hours after operation).
2. Disconnect negative battery terminal and wait 2 minutes before proceeding.
3. Raise vehicle using appropriate lift or jack stands to access the underside of the transmission bellhousing area.
4. Ensure adequate lighting and access to the driver's side of the bellhousing.

Procedure

1. 1

   Locate the crankshaft position sensor
   From underneath the vehicle, locate the crankshaft position sensor mounted near the rear of the engine block at the bellhousing area. The sensor is a compact unit with a single electrical connector. It is secured by a mounting flange and reads the crankshaft reluctor/target wheel. Confirm exact location and orientation against the factory service manual before proceeding.
2. 2

   Disconnect the electrical connector
   Press the locking tab on the sensor electrical connector and pull the connector straight away from the sensor. If the connector is difficult to remove due to corrosion or age, gently wiggle it while pulling. Do not pry against the sensor body itself as this may damage the sensor mounting threads or the connector housing.
3. 3

   Remove the sensor mounting bolt
   Remove the fastener that secures the crankshaft position sensor. Verify the correct socket size and whether the sensor uses a bolt-on flange or a threaded body against the factory service manual before removal. Place any hardware in a safe location for reinstallation.
4. 4

   Extract the sensor from the bellhousing
   Carefully pull the crankshaft position sensor straight out of the bellhousing bore. If the sensor is stuck due to heat cycling or corrosion, gently rotate it while pulling. Do not use excessive force or pry tools that could damage the bellhousing bore. Inspect the O-ring seal on the sensor body for damage or deterioration.
5. 5

   Clean the sensor mounting bore
   Using a wire brush or fine sandpaper, clean the sensor mounting bore in the bellhousing to remove any debris, corrosion, or old O-ring material. Ensure the bore is clean and dry before installing the new sensor. Inspect the bore for cracks or damage that could cause an oil leak.
6. 6

   Prepare the new sensor
   Inspect the new crankshaft position sensor for damage and verify it matches the original sensor design. Check that the O-ring is properly seated in the sensor groove. Apply a thin coat of clean engine oil to the O-ring to ease installation and create a proper seal. Do not use excessive oil or grease that could contaminate the sensor tip.
7. 7

   Install the new sensor
   Carefully insert the new crankshaft position sensor into the bellhousing bore, ensuring the sensor is properly aligned with the mounting hole. Push the sensor fully into the bore until the mounting flange is flush against the bellhousing surface. Verify the sensor tip does not contact the flywheel/flexplate teeth by checking clearance if possible.
8. 8

   Secure the sensor mounting bolt
   Install the mounting bolt through the sensor flange and thread it into the bellhousing by hand to avoid cross-threading. Tighten the bolt to the factory-specified torque (verify exact value in the FSM; typically in the range of ~106 in-lbs for a small sensor bolt). Do not overtighten as this can crack the sensor flange or strip the threads.
9. 9

   Reconnect the electrical connector
   Apply a small amount of dielectric grease to the sensor connector terminals if desired to protect against corrosion. Push the electrical connector onto the sensor until it clicks firmly into place. Tug gently on the connector to verify it is fully locked.
10. 10

    Reconnect battery and clear codes
    Reconnect the negative battery terminal. If a diagnostic trouble code (DTC) was stored for the crankshaft position sensor, it may need to be cleared using a scan tool, or it will clear itself after several successful start cycles. The engine control module may require a relearn procedure for the crankshaft position sensor signal.

Reassembly

1. Ensure the sensor mounting bolt is tightened to specification to prevent oil leaks from the bellhousing.
2. Verify the electrical connector is fully seated and locked to prevent intermittent sensor signal loss.
3. Lower the vehicle carefully and remove jack stands or lift supports.

Verification

• Start the engine and verify it starts normally without extended cranking or rough idle.
• Check for any diagnostic trouble codes (DTCs) related to the crankshaft position sensor using a scan tool if available.
• Observe the tachometer gauge to confirm it reads properly during idle and acceleration, indicating the sensor is sending correct signals to the engine control module.
• Inspect the sensor area from underneath for any oil leaks around the sensor mounting location after the engine has reached operating temperature.
• Test drive the vehicle to ensure smooth acceleration and no hesitation or stalling issues.

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