It should be check after the fuel filter and it should be approximately 37 psi.
fuel pessure test
no the 85 it is on the fuel pressure reg it should be the same
in the fuel tank
Yes, it is in the fuel tank.
Where is the fuel injector located?
The original fuel injectors on that model were recalled - did you ever have them replaced?
It is located inside the fuel tank.
drop the gas tank...pull the fuel mod out and replace the pump
You can find the 1987 Nissan 300 your pump relay switch in the fuse box. The fuel pump relay switch will be at the top of the third column.
That info is on pages 18 and 19 of the EF(Engine fuel) & EC(Emission control)section of the 1987 Nissan Truck/Pathfinder service manual.
in front of the right rear wheel attached to the frame
It has an internal fuel pump, it should be under the back seat.