The modern automobile engine uses a number of sensors to help the vehicle's engine management computer do its job. On a 1997 Chevrolet S-10 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.
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.
