It is located on the backside of the engine. Go to youtube and type in how to replace camshaft sensor on 2005 Nissan altima and it will show where it is and how to replace it, that is how I did my one.
The Camshaft sensor is located under the cap and rotor of the distributor. This is a common failure on the 2.4L engine due to oil leakage into the distributor. how is the camshaft sensor replaced on 1995 Nissan altima. what other considerations are there.
The camshaft position sensor is located near the thermostat housing. You should replace the crankshaft position sensor as well. This one is much harder to locate....it is on the backside of the engine that is between the firewall and the engine block. Both use the same sensor.