Relieving the fuel pressure in your Mazda Protege is essential if you are trying to replace a fuel system component such as a fuel regulator, fuel filter, fuel injector or fuel pump. The fuel system operates at approximately 45 psi and can be dangerous if you open the fuel system without relieving the pressure. The procedure for relieving fuel system pressure is straightforward and can be accomplished in a matter of minutes.
Open the hood and prop it up.
Remove the fuse box cover.
Turn the cover over and read the fuse and relay diagram. Search for "fuel pump" on the diagram and locate the fuel pump relay in the fuse box.
Remove the fuel pump relay from the fuse box with your hands. If it is difficult to remove, you can use pliers to pull it out.
Attempt starting the engine about three times; the engine won't turn over because it isn't getting fuel. Crank the engine for approximately five to 10 seconds and stop. Then repeat two more times. This has purged the fuel system of any residual fuel stored in the system and has depressurized it, making the car safe to work on.
