Where is the crank position sensor located on a 1988 Pontiac 6000 le?

It depends on the engine... 2.5L is located under the coil pack/Ignition module on the rear of the motor. 2.8L is located on the rear of the motor, under the rear exhaust manifold. Be careful when taking out the sensor, it has a very small bolt holding it in, and the sensors are known to break off in the block. Very big pain to get the remnants out.