I need to put a crankshaft sensor but I don't Know its location I already changed the cam sensor. Ronnie

no engine told nor country.
the cam sensor CMP is big time error , means fix me. but is not bad it is cam slip making CMP lie.
the cam belt is bad and screams,.
if this is belted cam engine DO NOT DRIVE It , but do fix that.
if DOHC engine for sure do not run any DOHC engines with cam belt loose.$$$$$$$$$$$$$$$$$$$$$
the list if interference engines states

Nissan
• All Interference

Here is the sensor location on the 2005 STS. My understanding is that on the 2005 it sat over the exhaust cam sprocket and on the 2006 it sits over the intake cam sprocket. That should be no problem as there will only be one to locate on your 2008.

if we are talking the 5.7L camshaft sensor is built intoto the distributor. It is replaceable. Crankshaft Sensor is located front of engine on bottom, right at the Harmonic Balancer. it is easily replaceable.

depends on the year and model. for example, on my 97 Grand Cherokee Laredo 4.0L , the cam sensor ( also called pick up relay or coil ) is underneath the distributor cap and rotor. flat, round, plastic device with a magnet and little wire (2) with plastic connector. the crank sensor is on the top left ( driver side ) , backside of the bell housing of the transmission. easy to find if looking up at transmission from underneath jeep. wire harness runs by it. will need a couple of long handled extension bars to remove bolt holding it in. do not forget to put little gold bracket back on with new part. this acts as a spacer as well as for support. you can look up more specific info for your vehicle on e-how.com. just type in for example : signs of a bad cam sensor on what year vehicle, how to change the part on vehicle etc.

checked the spark plug wires if is cracked P0340 is no cam signalat the PCM is. The camshaft position sensor information, along with the crankshaft position sensor information, is used control the fuel injection synchronization. The excess heat from the catalytic converter indicatesunburned fuel going out the exhaust. The catalytic converteris designed to burn any fuelleft in the exhaust. It sounds like your injectors are definitely out of sync dumping raw fuel out the exhaust. Since youreplaced the both the sensors and the PCM, it sounds like a wiring problem betweenone of the sensors and the PCM. Always use a digital multi-meter so you don't blow the PCM. Pull the cam sensor connector and check, with the key on, for about 8VDC on the orange wire (power from the PCM), and put the negative lead on the black/light blue wire (ground.) If you get about 8 volts both of those 2 wires are good. That just leaves thetan/yellow wire (sensor signal.) The signal should fluctuate 0 to 5 volts as the cam notches pass the sensor. To check the wire you would have to probe this wire at the PCM with all the connections put together, key on, and engine rotating (either by hand or with the starter.) The crank sensor wiring could be checked basically the same way. Overheating the cayalytic converter can cause the ceramic beads inside of it to crack, requiring replacement. Don't overheat the converters if you can help it. Turning the key on with a sensor unplugged will usually set an OBD code that will need to be cleared. It sounds like your on the right track. Let us know how it goes. P0340 Camshaft Position (CMP) Sensor Circuit P0344 Camshaft Position Sensor Circuit Intermittent
With a P0340 OBD-II trouble code, diagnosis can be tricky at times. Here are some things to try:

• Visually inspect all the wiring and connectors in the circuit
• Check for continuity in the circuit wiring
• Check the operation (voltage) of the camshaft position sensor
• Replace the camshaft position sensor as required
• Check the crankshaft position circuit as well
• Replace circuit wiring and/or connectors as required
• Diagnose/replace the PCM as required

both the single cam and twin cam engines use the teeth on the crank pulley for crankshaft sensor which is bolted in bracket attached to block near oil pressure switch, hopefully you didnt dent(bent) teeth on crank pulley from dropping it or putting pulley down a bit roughly because they bend really eazy.
also is the crank pulley bolted up in correct position?
is the timming belt tension correct from when you did cam belt?
if tension wrong or timming out by a tooth it will set crank sensor codes, even possibly cam sensor codes and if you get timming out more than 3 teeth either way(advanced or ********) you will bend valves.

I don't know about the cam sensor, but the crankshaft position sensor is located just behind the crankshaft pulley, or possibly even right on the pulley. Should be just a small little thing with a couple small bolts holding it down. If you are changing it out, just be very careful to get it reinstalled in exactly the right position, they can be very finnicky.

You are incorrect sir. There is a very good Youtube video showing you exactly where it is that is how I changed mine. The Crankshaft is located behind the engine block below and around from the cam sensor which is easly spotted looking at the engine. The crankshaft is in a difficult spot but once you figure out where it is it's easy...ish hope this helps

the camshaft position sensor is right around the crankshaft. there is a magnetic wheel at the end of the camshaft that the sensor uses to produce the signal.

cam sensor fires the injectors to synchronise injector pulsing with the spark at the spark plugs.. U need to probably change the crankshaft sensor (around the crank pulley) as the crank sensor is what controls the ignition spark.
hope that does it.
:)