How to Replace the Crankshaft Position Sensor in Vehicles

by Contributing Writer

The modern automobile engine uses a number of sensors to help the Vehicles engine management computer do its job. On a Vehicles pickup, one of the sensors is a crankshaft position sensor. The crankshaft position sensor tells the computer with the location the crankshift position and adjusts the ignition firing time and has other vital functions. When it goes out, it will need to be replaced quickly so the engine will operate optimally.

Under The Hood:

 How to Replace the Crankshaft Position Sensor in a Kia Optima

Raise the hood of the car and locate the crankshaft sensor. It is at the lower right of the exhaust manifold. The sensor is installed in the transaxle housing that is bolted to the engine.

Remove the single bolt holding the crankshaft sensor in place. Twist the sensor back and forth to unseat the O-ring seal. Pull the sensor out and unplug the wiring connector.

Lubricate the O-ring of the new sensor with mineral oil. This will aid in a smooth installation of the new sensor. Push the sensor into the location until it seats. Turn the mounting tab on the sensor until the mounting holes line up. Install the bolt. Snug the bolt, being sure not to overtighten and strip the threads in the aluminum transaxle housing. Plug the sensor connector into the engine harness connector. Start the engine.

Items you will need

  • 3/8-inch socket set

  • Mineral oil

 How to Replace the Crankshaft Position Sensor on a 2003 Mazda Protege

Loosen the right-front lug nuts with a ratchet and socket. Raise the front of the Protégé with a floor jack, and slide jack stands under its subframe. Lower the vehicle onto the floor jacks. Remove the lug nuts and pull the wheel from the front hub.

Remove the bolts securing the passenger-side wheel well liner, using a ratchet and socket, and pull the wheel well liner from the vehicle, exposing the crankshaft pulley behind it.

Find the crankshaft sensor next to the crankshaft pulley, toward the front of the vehicle. Press and hold the unlocking button on the crankshaft sensor’s wiring harness, and pull the Protégé’s wiring harness from the sensor’s harness.

Grab the crankshaft position sensor’s wiring harness and pull it away from the engine block firmly to disengage its retaining clip.

Remove the two bolts securing the crankshaft position sensor, using a ratchet and socket, and remove the crankshaft position sensor from the engine.

Position a new crankshaft on the engine, aligning the bolt holes on the sensor with those on the sensor. Hand-thread the two crankshaft position sensor bolts, then tighten them to 7 foot-pounds with a torque wrench and socket.

Route the crankshaft position sensor’s wiring so it is out of the way of all of the belts, then line up the clip on the wiring harness with its hole in the engine. Press the harness toward the engine to engage the retaining clip, securing the harness in place. Plug the Protégé’s wiring harness into the sensor’s harness.

Reposition the wheel well liner into the right-front wheel well, and hand thread its bolts. Tighten the wheel well bolts with a ratchet and socket.

Set the wheel back on the Protégé’s hub and hand thread the lug nuts. Raise the vehicle off the jack stands with a floor jack, and remove the jack stands. Lower the Protégé to the ground. Tighten the lug nuts, in a crisscross pattern, to between 65 and 87 foot-pounds with a torque wrench and socket.

Items you will need

  • Ratchet

  • Socket

  • Floor jack

  • Jack stands

  • Torque wrench

 How to Replace the Crankshaft Position Sensor on a Jeep

Raise the front of your Jeep with a jack and position a set of jack stands under the front axle to support it. Lower the jack, allowing the Jeep to rest solidly on the jack stands.

Locate the crank position sensor in the bell housing of the Jeep from under the driver's side. Locate and remove the two retaining bolts that secure the sensor to the bell housing, using a socket and ratchet.

Follow the wire from the sensor to the connector on the engine. Release the lock on the connector and separate the sensor wiring harness from the engine wiring harness. Remove the sensor and harness from the Jeep and discard it.

Position the new sensor on the bell housing and install the two retaining bolts. Tighten the bolts with a socket and ratchet until they are snug. Do not over-tighten these bolts or you will strip the threads out of the aluminum bell housing.

Route the wiring harness from the sensor to the engine wiring harness and push the two connectors together until the locking tab snaps in place. Be sure to route the wiring harness away from sharp edges or heat sources.

Raise the front of the Jeep off the jack stands with a jack then remove the stands from under the truck. Lower the jack and test the repair by starting the truck and verifying that it runs properly.

Items you will need

  • Jack

  • Jack stands

  • Ratchet

  • Socket set

 How to Replace the Crankshaft Position Sensor in a 2001 Chevrolet Silverado

Open the hood of the Silverado and disconnect the negative battery terminal with a small adjustable wrench.

Raise the truck on one side, using a floor jack, and place a jack stand beneath a solid point such as a frame rail. Slowly lower the truck onto the jack stand. Repeat for the other side of the Silverado.

Remove the transmission bell housing cover bolt, located beneath the starter motor, using a socket wrench.

Remove the white oil-level sensor connector, located beneath the starter motor, by squeezing together the locking tabs on its body and pulling it away from the sensor.

Remove the two large starter motor bolts, being careful to support the motor with one hand while using the socket wrench to loosen and remove the bolts. Carefully lower the starter.

Disconnect the wires on the starter with a box-end wrench, and remove the starter.

Disconnect the connector from the crankshaft position sensor, located above the starter mounting area, by prying back the locking tab with a flat-head screwdriver and pulling the connector away from the sensor.

Use the socket wrench to remove the sensor's mounting bolt, located next to the sensor, and pull the sensor from the engine. Installation is the reverse of removal.

Items you will need

  • Small adjustable wrench

  • Floor jack

  • Jack stands

  • Socket set

  • Box-end wrenches

  • Flat-head screwdriver

 How to Replace the Crankshaft Position Sensor in a 1997 S-10

Use the jack to lift up the front of the vehicle and set it on the jack stands. Be sure that the vehicle is completely and solidly on the stands prior to working on the vehicle. Crawl underneath the vehicle and locate the crankshaft position sensor. On the S-10's 4.3-liter V6, the sensor is directly underneath the crankshaft, just to the left of center. On the 2.2-liter four-cylinder engine, it's on the driver's side just below the coil pack.

Unclip the wiring harness connection to the sensor using your hands. Then unbolt the retaining bolt on the bottom of the sensor, using the ratchet. Remove the sensor with an open-end wrench and discard it.

Apply a thin layer of engine oil onto the rubber O-ring on the end of the replacement sensor. Then install the sensor in the engine block with an open-end wrench and tighten down the retaining bolt with the ratchet. Lower the truck off the stands with the jack.

Items you will need

  • Jack

  • Jack stands

  • 1 quart of 10W-30 engine oil

  • 3/8-inch ratchet and socket set

  • Open-end wrench set

  • Replacement crankshaft position sensor