I have a 1987 nissan maxima and i smell fuel everytime i get out of the car coming from the rear.

Nissan does not have a fuel shut of switch, that is ford. it does have a fuel shut off relay.

You have a gas leak somewhere of the tank vent system is leaking or blocked. You need to follow the fuel pipes and vent pipes to find the problem. Some Nissans did have problems with their vent systems, but whatever you do proceed with caution and watch what light source you use.

check for gas leaks thats a older car look under car while its running see any gas leaking lift hood is the gas smell stronger under there look on fuel line around carb

it is reset everytime u unlock the driver or passenger door with the remote or the key, other than that there is no reset button.

turn on acc and listen to pump see if you still smell gas poss.not venting properly

The MAF sensor is just about dead. Replace it and it should be fine again.

Sounds like a bad fuel pump, check if the smell comes under the rear wheels and also check for a loud humming noise when the key is turned to on. Those are signs of a bad fuel pump.

The fuel pump is located under the rear seat. You will need to remove the rear seats to gain access for replacement or inspection of the pump.

run scanner for trouble codes, some auto parts store will do this for free, have fuel injection system cleaned

1st I hope you are taking the fuel pressure from the correct side of the system. The correct side will be the side coming from the fuel filter and before the fuel pressure regulator. At a normal idle, the pressure should be roughly 30-33 psi. When you crack the throttle rapidly, a sudden vacuum drop will cause the diaphragm in the fuel pressure regulator to shift causing the fuel pressure to jump sharply. Usually to 45 or 50 psi. You can check the maximum fuel pressure by dead heading the pump. This can be done by simply pinching off the return hose to the fuel tank. At an idle, the maximum fuel pressure the pump will put out will be displayed. You will also notice a slight jump in rpm's because it cause the fuel mixture to fatten up before the ECM can respond to changing the pulse width based off of the o2 sensor.
I hope my answer was satisfactory.