The fuel pressure regulator is leaking gas

Every service manual describes how to relieve fuel pressure but we rarely do that. When customers are paying us by the hour, we don't have time to spend on things like that. There isn't that much fuel that's going to spray out, especially when the regulator is already leaking. The same is true when replacing fuel filters. We just pop a hose off and let the fuel run on the ground. You'll only get a few tablespoons. You can also look for a fuel pump fuse. Remove it, then try to start the engine. You can also look for a pressure test port on the fuel rail and use that to bleed off the pressure. Check out the diagrams (Below). Please let us know if you need anything else to get the problem fixed.

The fuel pressure regulator is located at the end of the fuel rail with the fuel injectors. It will have a vacuum line attached to it. If you want to check it install a fuel pressure gauge see what the pressure is at running(53-59psi) unplug the vacuum line and if it is working the pressure should increase 3-5 psi. That means its working. Or test it with a vacuum pump, apply 12-14 in of vacuum, should hold vacuum. Post back with any other questions.

Relieve the fuel system pressure.
Disconnect the negative battery cable.
Remove the vacuum hose from the regulator.
Place a rag under the connection and remove the fuel return pipe clamp.
Remove the fuel return pipe and O-ring from the regulator. Discard the O-ring.
Unfasten the pressure regulator bracket attaching screw, then remove the pressure regulator assembly and O-ring. Discard the O-ring.

Hello,

In the diagrams down below I have included the description of operation and the instructions for the removal and installation of your vehicle's fuel pressure regulator[including a diagram of it's location] from the vehicle manufacturer for you. Please go through this guide and get back to us with how everything turns out, and I hope that this helps out.

Thanks,
Alex
2CarPros

Hello again,

Please check the o-rings that seal the injectors. This could be a possibility that one is leaking and letting fuel leak into the throttle body that way. Also, has the vehicle been in service or has it been sitting for a while?

Thanks,
Alex
2CarPros

Hello,

This sounds like either an electrical problem or it could be an intake/vacuum leak. Let's start with the latter. If this was an intake/vacuum leak then it would be letting unmetered air into the air intake system. Unmetered air is defined as air that enters the air intake system from the Mass AirFlow sensor[MAF] to the combustion chambers of the engine. The Power-train Control Module[PCM] will get a lean signal from the O2 sensors and will over adjust for this by holding open the fuel injectors longer causing a rich condition. Here is a link below explaining how to find a intake/vacuum leak below:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Please go through this guide and get back to us with what you find out.

Thanks,
Alex
2CarPros

Hello again,

I'm 99.9% sure that you've found your problem. The PCM will still fire that fuel injector and without a spark plug to ignite it, the air:fuel mixture will get shot out of the exhaust and the O2 sensor will read it as being rich. It will cut fuel to the other injectors causing them to run lean and it will affect performance. I would suggest unplugging the fuel injector connector from the problem cylinder until the new spark plug wires arrive. It will make no difference as it is a dead cylinder anyway, the short and long fuel trim will normalize and you will save gas. Please keep us informed as to how everything turns out.

Thanks,
Alex
2CarPros