Taking the cap off the cam sensor will expose the brass colored reluctor ring (rotor). This ring has a "window" machined in it. It’s the spot where the ring stops as it does not make a full circle around the top. This gap will trigger the hall effect sensor that is housed in the cam sensor cap.
From Wikipedia (The Hall effect sensor is used as a direct replacement for the mechanical breaker points used in earlier automotive applications. Its use as an ignition timing device in various distributor types is as follows. A stationary permanent magnet and semiconductor Hall effect chip are mounted next to each other separated by an air gap, forming the Hall effect sensor. A metal rotor consisting of windows and tabs is mounted to a shaft and arranged so that during shaft rotation, the windows and tabs pass through the air gap between the permanent magnet and semiconductor Hall chip. This effectively shields and exposes the Hall chip to the permanent magnet's field respective to whether a tab or window is passing though the Hall sensor.)
The metal rotor of the cam sensor is driven by the cam gear as it rotates. The cam gear is driven by the crankshaft timing chain as it rotates.
When the cam sensor is pulled out you can see the oil pump shaft. The oil pump shaft has a notch or slot machined into the top. The bottom of the oil pump shaft disappears into the lower part of the timing cover where the oil pump is housed. On the bottom side of the the cam sensor shaft you can see the flat head (like a flat head screwdriver) that mates into the oil pump shaft. So the cam sensor drives the oil pump.
I know you didn’t asked but I thought I would keep going.
Install the cam sensor in the block with the cap OFF. When the cam sensor is fully seated in the block, the window of the rotor should be pointing approximately to the driver head light. To accomplish this, you need to notice the direction of the oil pump shaft slot and the bottom mating head of the cam sensor. Using a long screw driver turn the oil pump shaft so that when the resting orientation of the cam sensor is final the two mate. As you install the cam sensor, the cam sensor gear will mesh with the cam gear. Shine a flash light into the cam sensor block hole and you should see the cam gear. The meshing of the two gears will rotate the cam sensor slightly clockwise, hence the term "resting orientation". When the cam sensor is fully seated in the block the cam sensor rotor will be stationary (for the cam gear is not moving). Grab the rotor and try to turn it, you should not be able to. The outside housing of the cam sensor will still rotate. I now install the locking bolt and washer that locks down the cam sensor (keep it loose, do not tighten at this point). Now you can install the cap that houses the Hall Effect sensor. The cap will only go on one way. The cap has a small notch that mates to a notch in the outside housing of the cam sensor. These notches ensure the cap is installed win the correct orientation and will not spin until you tighten down the cap screws. LOOK the whole install idea here is than when that you are going to spin the cap counter clockwise so that the Hall effect sensor travels along the rotor until it comes to the window of the rotor. Once the Hall effect sensor is past the first edge of the window it will send out a “Hey I found the window voltage (actually the voltage drops at this point)” Keep turning it counter clockwise and the Hall effect sensor will go past the remaining edge of the window, and say “DAM no more window”. WHAT YOU WANT IS THE FIRST EDGE OF THE WINDOW.
So look at the cap and see were the hall effect sensor is and turn the outside housing so that when the cap is placed on the outside housing the Hall effect sensor is just before getting to the window in the rotor when turning it counter clockwise. Then all you have to do to find the window is turn it a small amount counter clockwise. When you find the window the red LED in the caspers cap illuminates. Now you can lock down the locking bolt and washer that secures the cam sensor to the block. This prevents the cam sensor outside housing from spinning anymore. From now on the motor will drive the rotor clockwise and so the point of view changes in that the rotor window is looking for the Hall effect sensor.
When the engine is running, the cam senor rotor “window” is turning. When the window reaches the hall effect sensor, a negative pulse, which may be inverted somewhere, is sent to the computer to activate #6 cylinder injector due to the Buick V6 firing order.
