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Need Help Relieving Fuel System Pressure - 1984 Thunderbird Turbo Coupe

I’ve recently acquired this vehicle. It does not run and is currently considered a project car.

The former owner told me the car needed new fuel injectors.

The key was turned on today, but the motor was not cranked over. This pressurized the fuel system. The injectors are leaking fuel all over the intake manifold, hours after the key was removed from the ignition and turned off. For some reason, there is a tremendous amount of pressure in the fuel system even after the key is turned off for hours. The leak is coming either from the fuel rail to injector seal or the injector to head/manifold seal.

I found a shrader valve on the firewall. It’s just above the windshield wiper motor. I removed the cap and depressed the valve, thinking this would burp fuel out for a split second and that would immediately depressurize the fuel system. Well, 2 minutes later, and nearly 1/2 gallon of fuel, the system is still under very high pressure.

How do I relieve the fuel system pressure?

Obviously, since this car does not run and it’s a project car, the injectors and all seals will be replaced. But for the time being, I need to get the pressure out of the fuel lines, rail and injectors to prevent this car from leaking gasoline all over and becoming a very dangerous fire hazard.


The only thing that can pressurize the fuel system is the fuel pump. Pull the fuel pump fuse or disconnect the battery. That should stop the leak. Don’t reconnect the battery until the fuel leak is fixed.

I hope you have a service manual for this car. If not, you need one.

A friend of mine had one of these cars. It was fun to drive, and I think it’s an unappreciated classic.

I wish you the best of luck, and please post pictures of your T-bird.

It’s old and faded. Nothing much to look at right now. Will probably take years to get it back into shape.

Problem solved:
It’s the fuel pressure regulator on the end of the fuel rail. Bad diaphragm.