Crankshaft Sensor Installation in a 1991 Grand Am

The 1991 Pontiac Grand Am came in three different trim levels: base, LE and SE. Pontiac offered each trim level in either a coupe or sedan body style, giving customers a wide selection from which to choose. The base-level sedan and coupe models of the 1991 Grand Am came with a 2.5-liter, four-cylinder engine that cranked out 105 horsepower. Replacing the crankshaft position sensor on the 2.5-liter engine is an interesting task, as it connects to the direct ignition system, which means you first must remove the DIS to access the sensor.

Instructions

1

Look on the drivers side rear of the engine and find the direct ignition system the assembly that holds the ignition coil packs and ignition control module. Press and hold the unlocking buttons on the DIS assemblys wiring harnesses, then unplug the harnesses.

2

Remove the three bolts securing the DIS assembly to the rear of the engine using a ratchet and socket. Pull the DIS assembly from the engine, leaving the spark plug wires attached to the coils, until you see the sensor attached to the underside of the DIS assembly; this is the crankshaft position sensor.

3

Remove the two screws securing the crankshaft position sensor to the DIS assembly using a ratchet and socket. Pull the sensor from the DIS assembly using a slight wiggling motion.

4

Align the receptacle on the new crankshaft position sensor with the prong on the DIS assembly and press the sensor into the DIS assembly. Thread the two crankshaft position sensor bolts to 20 inch-pounds with an inch-pound torque wrench.

5

Apply a thin coat of new engine oil to the crankshaft position sensors O-ring and line up the sensor with its hole in the engine block. Guide the DIS assembly back onto the engine and hand-thread its three bolts. Tighten the DIS assemblys bolts to 20 foot-pounds with a torque wrench and socket. Plug the wiring harnesses into their respective receptacles on the DIS assembly.