Fuel Pressure?

[cschulzy]

I have a stock 89 GT 5 speed. It has been sluggish for a while so I thought I would check the fuel Press. Turn the key to on and press is 15 psi. About 3 seconds after it hit 15psi I can here a klick and press drops to zero in les that 10 seconds. At idle vacuum connected press is 30psi. Turn the engine off and press drops to zero in less than 10 seconds.

The injectors were cleaned about 18 months ago and the fuel pump is about 2 yrs old.

Is my fuel press ok or should I be looking to replace some components. I used a direct reading guage connected to the shrader valve test port on the fuel rail.

Thanks for your time

Chris

[Dark_5.0]

After I kill my car it will usually hold fuel pressure for hours and hours but nothing in my fuel system is stock.

The 30 psi reading with the engine running and the vacuum line connected is right were it should be.

[PKRWUD]

The fact that it bleeds down so fast is not good. It will lead to hard starts, with long cranking times.

Follow the fuel line from the schrader valve back towards the fuel tank until you find a section of the fuel line that is rubber. With the engine idling, and the gauge hooked up, have a friend turn the engine off, and at the exact same moment, clamp the fuel line where the rubber hose is. You can use ViseGrips if you don't have anything else. The purpose is to seal off the supply hose completely, instantly, when the engine is shut off. Upon doing this, observe the gauge. If the pressure bleeds down quickly, just like before, remove the vacuum hose from the regulator, and look for any signs of fuel. If you find any fuel in the vacuum line, replace the regulator. If you don't, repeat the part with your friend, and the engine running, only this time, when he shuts off the engine, clamp the fuel line where it goes from the right bank of injectors to the left bank. If the gauge leaks down, you either have a bad fuel pump, or a cracked fuel line inside the tank. If the gauge becomes steady, or leaks down much slower than before, you have leaky injectors, and they need to be replaced.

[cschulzy]

Thanks for the help. When I first start in the morning it will start straight away but splutters abit then settles down to a smooth idle. Its like the cylinders light up 2 at a time.

The fuel out here is really crap and I change the filter every 6 months. I'll try your tricks and let you know how it goes. I hope its not the fuel pump. Its a pain to drop the tank. I should have cut an access hole the first time I had the tank out.

Thanks again

Chris

[Ex4bangerStang]

Cutting Access Holes??? Big No No...Instant Fumes from Gasoline get in the car that way which leads to unsafe driving.