had same question, and found the answer at:
http://media.Photobucket.com/image/2001%20nissan%20maxima/Nelsito65/CaliSpec_Exhaust_S.png?o=22
On a 2005 Nissan Maxima where is the Camshaft Position Sensor (Bank 1) located?
where is bank one sensor 1 located on 2001 maxima Bank 1 sensor 1 is located at the upper front left hand side of the motor. My 01 20th anniversary edition has 4 sensors. Just recently replaced all 4.
The MAP sensor is mounted at the rear of the left-bank (front) cylinder head.
Bank 2 Sensor 1 located downstream left front rear side.
Bank 2, Sensor 1 is located on the front of the engine(radiator side), before the first catalytic converter.
Bank one is generally the cylinder number one side or drivers side on many cars, sensor 2 would be the rear, or post catalytic converter side of the bank 1 manifold.
Bank 1 Sensor 2 is located in the front of the engine, on the left side toward the bottom. It has a 3 pin plug that is located in front of the engine just under the plastic engine cover.
Check this site out, it shows you. http://www.nissanhelp.com/diy/maxima/projects/nissan_maxima_o2_sensor_identification.htm
: Research shows that bank #1 is the side of the engine where number 1 cylinder is located. On a 2001 Nissan Maxima that is on the back side or firewall side of the engine. That makes bank #2 the front or radiator side. == ==
bank 2 sensor 2 front bank after the cat
the bank 1 sensor one is located up steream on the exhaust manifold eo next to the engine
Bank 2 Sensor 1: Located on front exhaust manifold pipe nearest the radiator. Hard to reach without specific tools. Clip located in front of engine compartment.