I have a 2003 newmar with a cam sensor code. what could be the problem

Know the Code!
Without further information?!!
Ya Can't believe the Check Engine light until
the System Voltage in a Motor Home or other is correct;
Too High, the Alternator Voltage Regulator is Bad or Too Low because, something (left on) is draining the system voltage down
or Bad Battery connection.

Always, Check the Starting Battery for 12.6 Volts (disconnected) first before coming to any real conclusions.
Reconnect Battery AND Check for 14.0+/- .02 Volts running
all systems OFF.
IF LESS THAN 12.6 and or LESS THAN 14.0+/- .02 Volts running
Check the Alternator, is it making a Low pitched whistle sound?
Is the Alternator Hot or is it Cold?
Hot=Low system voltage
Warm=operating normally
Cold=Not working at All
Low pitched whistle sound=Charging (System voltage too low).

After start/Shut off a few times as well as running a while as you normally would drive, Check all Low voltage connections around the starting Battery for warmth, those that are warm are High Resistance and either need a bigger Cable or the connection Cleaned or replaced.

IF ALL IS WELL:
NEXT, Disconnect all Batteries for 20 minutes and reconnect
This will remove the Code, Drive and see if the code comes
back.

If the code comes back, read on...

Check the work of the last service done, Done right?
Or is it time for a Tune up?

All the above are things you can check without tools
and should be on your everyday check list (Right below the line that says check Battery fluid levels) before taking your Motor Home anywhere!

Diesel; I'd say the fuel pump timing is off as programed in the
Fuel pump Program control Module (FPCM) Either
Reprogram, Reprogram by Disconnecting Fuse for an
hour or Replace Module.
Possible low Lift Pump pressure, wrong Fuel filter/
dirty Fuel Filter. Crank Shaft Sensor... Same as Gas

Gas; I'd say the Valve timing chains need to be replaced
if high mileage or a Bad camshaft position sensor or
Crank shaft sensors. The Sensors are like a CD player
optical pickups, which need be cleaned from time to
time (Use a soft lens cleaning cloth). Remove a Sensor,
clean the Crank shaft Harmonic balancer 360 Deg
and slide cloth between the sensor position and the
crank shaft. Gently Clean the Sensor and reinstall.

Dodge and Chevy have front and Rear Crank Shaft Sensors.


You NOW, Know the Code?


What the P0341 code means. P0341 is an OBD-II generic code that says the engine control module (ECM) detected the engine camshaft position sensor circuit is not within specifications. The sensor pulses do not correlate to the pulses of the crankshaft sensor.


Error Code P0342 is defined as Camshaft Position Sensor "A" Circuit Low. This means the CMP (camshaft position) sensor circuit on engine bank 1 sends an irregular reading. It's a generic trouble code, meaning it applies to all vehicles equipped with OBD-II, particularly vehicles made since 1996 up to present.

P0343 trouble code definition. A P0343 trouble code is related to a vehicle's timing system and the camshaft position sensor that monitors the rotation of the camshaft to relay data to the engine computer so it can calculate the appropriate amount of fuel and ignition.


P0344 code definition. Diagnostic trouble code (DTC) P0344 is a generic powertrain DTC that covers all makes and models of vehicles manufactured starting in 2003. This code occurs when an incoming signal from the camshaft position sensor (or sensors) is missing at one point or another when it should not be.Dec 21, 2018


Crankshaft position is used to inform the Engine Control Module (ECM) of when it is time to spark and deliver fuel. ... Trouble code P0345 is set whenever the ECM does not sense crankshaft pulses or senses a problem with the pulses in the output with Sensor "A" Bank 2.Aug 1, 2018

There ya go FREE, no Charge!
Have fun cleaning and Let me know how it all turns out...