the gray thing is the mass air meter, the sensor is the black thing that will be sitting on the top of it, to take that off you need a torx bit screw or you can just spray cleaner through the end of the meter.
yes the wires are the actual thing you need to clean, just spray them w/ the cleaner, you can GENTLY !!!!!!!!!! rub them w/ a Q-tip if you choose to but sometimes just spraying the cleaner works.