It mounts in the rear manifold at back of motor just after the 3 cylinders piping converges into the single outlet - there will be a silver cover on it and a wire (usually black that comes to a connector about 6 " away. You can use a wrench (about 1" size) or a specific tool to remove it. Do this with engine cold or the threads will risk being damaged. The new sensor comes with special beaded lubricant for thethreads on the O2 sensor. Be sure to use it BUT be careful not to get any on the sensor itself. The job can be bit aggravating but not too terribly difficult.
Yes
The speed sensor is not expensive and is easy to replace.
I should be just above the brake pedal where the shaft of the pedal pushes up against the switch. It should be easy to adjust or replace
You need to remove the serpentine belt and alternator in order to get the crank sensor; one 10mm bolt holds it. It is easy to replace.
The replacement of a MAF sensor will be different for vehicle models and brands. The MAF sensor bolts onto most engines, and is easy to change.
Back by the fuel tank itself, look around and it is easy to get and replace
Is it easy to replace a throttle body in an 88 sentra? How do you clean a throttle body
easy take old one off replace with new one! simples no
You have to first remove the transmission oil pan and the valve body. The Range sensor is relatively easy after that.
no
Easy fix!
Assuming the oil level is ok but the oil light still comes on: The oil level sending unit or sensor needs to be replaced - not too expensive and relatively easy to replace,