You mean cam sensor? I think they started using one on each head in 05, not sure why. I think they have different part numbers, so they might not be interchangeable.

http://www.google.com/imgres?imgurl=...9QEwAQ&dur=800

As for knock sensors, the 4.6 3v has two.

 

You really need to check the voltage when the car is running, and watch or log it. If it drops into the mid 12'v range when running, that code will get thrown. The alternator is usually the cause of such low voltage.

And be sure to clear the codes, as it won't go away on its own (unless you've unhooked the battery for at least 20 minutes).

 

Or do what I did.

Recently because the cam position sensor code was coming up (about weekly) I got a 200amp PA performance alt and an upgraded batt-to-alt wire.

Combine that with the red top I put in when the prevoius battery died and I think my electrical system is solid now.