In the 1999 model year, Oldsmobile took a step toward the younger crowd with the release of the small and sporty-looking Alero. Even the Alero couldn’t save Oldsmobile, as it was the last Oldsmobile to roll off the 106-year-old automaker’s assembly line in April 2004. The 2001 Alero came in five trim levels, and all but the base GX trim level came in either a coupe or sedan. A 150-horsepower, 2.4-liter four-cylinder engine came standard on the 2001 Alero GX. Replacing the crankshaft position sensor on the entry-level engine is a straightforward task most do-it-yourself mechanics can perform.
Raise the front of the Alero with a floor jack and slide jack stands under the vehicle’s subframe. Slowly lower the car onto the jack stands.
Slide under the vehicle until you find where the oil filter mounts to the engine block, near the front of the car. Find the crankshaft position sensor just above the oil filter.
Pry upward on the locking tab on the crankshaft position sensor’s wiring harness with a flat-head screwdriver and pull the harness from the sensor.
Remove the bolt securing the crankshaft position sensor in the engine using a ratchet and socket. Pull the crankshaft position sensor from the engine with a slight twisting motion.
Apply a thin coat of fresh engine oil to the O-ring on the new sensor. Insert the new sensor into the hole in the engine and align the bolt hole on the sensor with the bolt hole in the engine block.
Thread the crankshaft position sensor bolt, then torque it to 8 foot-pounds with a torque wrench and socket.
Raise the Oldsmobile off the jack stands using a floor jack, and remove the jack stands. Slowly lower the Alero to the ground.
