How to Install a 3.1 Lumina Crank Sensorby Cayden Conor
The Chevrolet Lumina 3.1 engine uses one of two crankshaft position sensors -- a 3X or a 24X -- the X denotes how many signals per revolution of the crankshaft are sent to the computer. The 3X crank sensor only sends an ignition signal to the computer. The 24X sends an ignition signal, plus additional signals relating to the fuel injection, to the computer. Both crank sensor signals are used by the computer as a reference for the position of the crankshaft and to calculate rpm.
3X Crankshaft Position Sensor
Disconnect the negative battery cable and lay it aside, ensuring that it does not touch metal. Turn the steering wheel all the way to the left. Raise the front of the Lumina, using the floor jack, and support it with jack stands.
Remove the wiring harness connector from the crankshaft position sensor. The sensor is located on the back of the engine, near the firewall, near the ignition module. Remove the retaining bolts, using a socket, then pull the sensor off the engine.
Lubricate the new O-ring with engine oil, then slide it on the new sensor, then install the new sensor and tighten the bolts to 71 inch-pounds of torque. Plug in the crankshaft sensor. Lower the vehicle. Turn the steering wheel straight ahead. Reconnect the negative battery cable.
24X Crankshaft Position Sensor
Remove the negative battery cable and lay it aside, ensuring that it does not touch metal. Loosen tension on the serpentine belt by pushing the tensioner away from the belt, using a socket on the tensioner pulley bolt. Lift the belt off the crankshaft, but do not remove it from the rest of the pulleys.
Remove the harmonic balancer retaining bolt, the pull the harmonic balancer off, using special tool J 24420-B, which is available at any dealership. A harmonic balancer puller will also work to remove the balancer.
Unplug the wiring harness connector from the crankshaft position sensor. Remove the retaining bolts, using a socket, then pull the sensor off the engine.
Install the new crankshaft position sensor, then tighten the bolts to 8 foot-pounds of torque. Plug in the electrical connector. Reinstall the harmonic balancer, using special tool J 29113 or a harmonic balancer installer.
Smear the threads of the harmonic balancer bolt with thread sealer. Install the bolt and tighten it to 110 foot-pounds of torque. Lower the Lumina off the floor jacks. Reinstall the serpentine belt and reconnect the battery cable.
Things You'll Need
- Set of wrenches
- Floor jack
- Jack stands
- Set of sockets
- Torque wrench
- Special tool J 24420-B
- Special tool J 29113
- Thread sealer
Cayden Conor has been writing since 1996. She has been published on several websites and in the winter 1996 issue of "QECE." Conor specializes in home and garden, dogs, legal, automotive and business subjects, with years of hands-on experience in these areas. She has an Associate of Science (paralegal) from Manchester Community College and studied computer science, criminology and education at University of Tampa.