I have a 2002 Nissan Maxima 3.5 With code PO345 Bank 2. I understand this to be the cam shaft sensor. Which censor is bank 2? The one towards the radiator , or the one towards the Firewall?

Replace sensor A bank 2 with an OEM part.

You need to have a live data scanner hooked up to verify the powertrain control module (PCM) is actually receiving the signals from the CMP sensors you replaced, there is no more guessing here and no quick answers, it is a possibility the wiring harness and connectors to the sensors is defective, the wiring should always be replaced whenever the sensors are replaced on this engine ALWAYS, as they are frequently the problem and not the sensors themselves. But due to the difficulty of replacing the CMP's they both are replaced as a unit repair. Also it may be helpful for you to read the info at the link below. P0345 2005 Nissan Maxima Camshaft Position Sensor Circuit Bank 2

Here's a video on your sensor,this vehicle's engine is the same as your's. Replace Nissan 3 5L V6 Crankshaft Position Sensor

there is only one crankshaft sensor so you will be looking for a CAM shaft sensor for it to be on bank 2
go google and type in --location of cam shaft sensors on nissan altima engine ---

I am not sure what "slip n tcs" means but on the 2005 nissan maxima the code P0340 is for the camshaft position sensor circit on bank 1, which is in the rear of the engine compartment. Code P0345 is for camshaft position on bank 2, which is in the front of the engine compartment. The images show the Cyl banks and a cam sensor.

To review - - the intake valve solenoid valve controls the flow of oil thru the control valve to adjust valve timing.
The code means the computer "sees" the valve timing as out of range and/or not controllable.
Possible causes could be a defective or stuck solenoid valve, dirty oil causing a blockage, a faulty cam sensor or faulty crank sensor.
Other than changing the oil and filter, the components would need to be checked with a scanner that can look at live data.

did you have a cam sensor stored?? and also which bank sensor did you replace?? bank 1 and bank 2 can be easily mixed up. well not mixed up, but bank 1 is by the firewall. bank 2 is at the radiator. you may have replaced bank 1 instead of bank 2. so when you remove the air box to replace sensors and you are lookin at the connectors, bank 1 is the one on the right side head. bank 2 is the left side head if you are looking at it from air box side. if you are looking at it from crank pulley side, bank 1 is on the left and bank 2 is on the right head. what code do you still have stored??

bank two is the bank of cylinders that is closer to the radiator...not the firewall side.

There are 2 on this vehicle one on eitherside of engine. Left and right or bank 1 and bank 2 Consider taking it in for correct diagnosis.