Replacing the Crankshaft and Camshaft sensors on a 1991 and later Buick Park Avenue

If your car is misfiring in a rhythmical pattern when you first start it up for the day or dieing when engine is hot, it could mean your Camshaft or Crankshaft sensors need replacement.


Important, disconnect negative cable from the battery before doing any work on electrical system. Wear safety goggles.

Tools recommended:
Break Bar, Torque Wrench, ratchet driver and a full metrics ratchet socket set, one Q tip, large straight blade screwdriver, ratchet extension and adapters if needed.

First we'll start with the easiest and cheapest of the two sensors.


Replacing the camshaft sensor:
The camshaft sensor is located on the right side of the engine, behind the water pump pulley.

1. Loosen the screws to the water pump pulley with a breaker bar before removing the serpentine belt. Always turn counter clockwise to loosen.

2.Remove the serpentine belt via the belt tension-er.

3.Use a regular ratchet driver to finish removing the belt pulley from the water pump.

4.Remove the bolt holding the camshaft sensor in place and disconnect electrical connector. Secure the connector with a clothes pin so you don't lose it down in the engine compartment. Clean around the sensor to avoid getting dirt in the engine.

5. Pull the camshaft sensor straight out with a slight twisting motion.

6. Lightly lubricate the O-Ring on the new sensor with fresh motor oil, and install in the engine.

7. installation is the reverse of removal.


Crankshaft Sensor:

1. Jack up the front passenger side of the car and safely support it on jack-stands.

2.Remove the tire, remove the inner tire well splash guard cover.

3.Before removing serpentine belt, loosen the center bolt on the harmonic balancer/vibration dampener. (crankshaft pulley)

4. Remove serpentine belt via the belt tensioner.

5.Finish loosening and remove the bolt from the harmonic balancer.
Have an assistant help you, using care not to let the weight of the harmonic balancer rest on the bolt as it can be damaged. Gently pry it of with a straight blade screwdriver. Leave the woodruff key in the crankshaft. Use care to not damage the crankshaft during removal as oil leakage could result. Mark the relationship between the crankshaft and the pulley, so you will be able to line the pulley up just right during re -installation.

6. Disconnect the electrical connector from the crankshaft sensor, secure the connector with clothes pin and loosen the bolts holding the sensor pedestal in place.

7.Separate the old sensor from the pedestal, and install the new sensor, just the same way the old sensor came out. Using the suggested crankshaft sensor alignment tool on the back of the harmonic balancer, making sure the fins on the harmonic balancer pass through the sensor's slot and don't hit it. If any fins on the back side of the harmonic balancer are bent, damaged, or missing, replace the harmonic balancer assembly.

Installation is the reverse of removal. It is imperative the crankshaft sensor be aligned properly before engine start up to avoid damage. Use care not to over tighten bolts during installation. Always tighten to manufacturer's recommended torque.


Harmonic Balancer/Vibration dampener