Nissan Repair: oil light on Nissan sunny FB14, oil pressure sending unit, main bearings

Question
Hi i have a Nissan sunny FB14 model. the oil light of late doesnt go off. Would you have any idea about what the problem could possibly be. There is enough oil.

Answer
Tom,

There are only two things that could be wrong.  The first is bad and that is the oil pump does not put out enough pressure.  This could be caused by the bearings being worn out or the pump could be worn out too.  The second is that the sending unit is plugged up.  What you do for the cheap test is to purchase a oil pressure sending unit for your car that is for the light and install it.  If the light goes off the pressure sending unit was defective or plugged up.  If the light does not go out you will need to get a pressure gauge and check the oil pressure.  If the pressure is within specifications you could change the oil to a heavier grade like if you are using 5W30 go to 10W40 and see if the light goes out.  If not you are going to have to replace the pump and or change the rod and main bearings to get the tolerances within specification and that should increase oil pressure to within specifications.