Where is the crankshaft sensor on a 3.8L in a 97 buick lesaber
The sensor is located to the right of the crankshaft behind the vibration dampner (harmonic balancer). You will need a balancer puller and a special tool to space the new sensor correctly.
(can be done also with eye spacing, but the tool is recommended to ensure proper spacing as to prevent damage to new sensor and / or harmonic balancer.) You will also need a strap wrench to hold balancer pulley in place while removing and re-installing balancer to crankshaft bolt. (helper required)
Procedure for replacement:
Remove negative battery cable.
Set parking (emergency) brake.
Release tension on serpentine drive belt and remove belt from harmonic balancer pulley. ( large pulley at bottom of engine)
Break loose lug nuts on passenger side front tire, do not remove bolts yet.
Raise and support vehicle on passenger side, remove wheel.
Remove plastic splash guard (cover) from passenger side wheel well.
Remove dampner / balancer center retaining bolt (counterclockwise, it is torqued very tight.) Use a strap wrench around pulley and have a helper hold that in place while using a 1/2" breaker bar and socket to turn pulley bolt out of crankshaft. Be careful not to rotate engine in a counterclockwise direction while breaking the bolt loose.
Using balancer puller, remove dampner / balancer pulley from engine.
You will now see the crank sensor to the right of the crankshaft bolted to the timing cover.
Disconnect sensor wiring and remove retaining bolts, remove sensor.
Put new sensor in place and screw in bolts, do not tighten them yet.
Reconnect wiring to sensor.
Now use special tool to properly space sensor. If you cannot find one at the parts store, you can space the sensor with the balancer pully held in place (not installed yet) and space the sensor evenly with the veins on the hub of the balancer pulley. Take your time and be sure it is as evenly spaced as possible.
Tighten sensor bolts.
Clean balancer hub free of any oil and dirt deposits using brake or carbeurator cleaner.
Reinstall balancer to crankshaft by tapping around the inner surface of pulley with a rubber hammer.
It is a press fit, so be sure you have it started evenly and progress slowly in a circular motion to ensure you are keeping it aligned straight with the crankshaft.
Reinstall balancer bolt using the same method as removal, torque bolt to 110 foot pounds, then tap around balancer again twice with rubber hammer, turn the engine 2 full revolutions clockwise using the balancer to crankshaft bolt, then tighten bolt an additional 1/4 turn.
Replace splash guard, put wheel on tightening lugs to finger tight and then wrench tight in a star pattern.
Lower vehicle until wheel makes contact with floor, tighten lug nuts to 115 foot pounds in a star pattern using a torque wrench.
Fully lower vehicle, remove jack.
Re-install serpentine drive belt
Re-connect negative battery cable.
End of procedure....Hope that helps!.....Mike
Jun 25, 2011 |
1997 Buick LeSabre