I am not a expert, but I think that the sensor in question is the crankshaft. It is located on the bell housing. If I am not mistaking, it will be located towards the driver side of the car. Jack-up the car and it is located between the oil pan and the bell housing ( transmission? ) From under the car, look straight up and you will see a thick black wire coming like from the upper part of the engine compartment then come down connected to side of the bell housing. You will see this so called sensor at the end. Now here is the problem. You need to have very skinny and long arms to reach this. Also you will need a large open wrench to unbolt the sensor. You will need one that is over 1". My biggest tool is a 1" and it is too small!!!

After unbolting the sensor, you just wipe off all of the **** it has and just put it back on! Make sure that the battery cable is not connected.
Now, I cleaned my CAMshaft sensor yesterday and my car still shakes in idle. The only thing that was accomplished was that the engine light did not come on again. So I guess I am in the right direction folks.
Hey, if anybody thinks I stated anything incorrectly, PLEASE let me know. I am in the process on doing this too myself as soon as I go to Sears to pick up some tools
