After sitting all night, my 2000 Taurus has no fuel pressure as measured with a fuel pressure guage. Consequently, it is hard to start. I can build up the pressure by turning the key on and off 3 or 4 times and then it starts Ok. The car runs fine otherwise after this. I believe that the fuel is being dumped back into the tank or through some of the fuel injectors.

Also, is there a check valve in the fuel pump?? I am also suspicious of the fuel pressure regulator that is in series with the fuel rail. Any ideas of what might be causing this??

 

From your description, my thought is the fuel pump itself is leaking off over night. There is a check valve in the pump to keep fuel in the lines. If the injectors were leaking, the fuel would go into the engine and end up in the oil pan. Let us know.

 

This is a good thought and I might have to replaced the fuel pump. The easiest thing is to replaced the fuel pressure regulator as it is located in the engine compartment. I have order this part and will report the results. I appreciate your input

 

I have replaced the fuel pressure regulator and these are the results:
Fuel pressure while engine is running: 30 psi
Fuel pressure after sitting overnight: 15 psi
The car starts somewhat better, but the weather is warmer and the problem usually occurs when the temperature is colder.
I suspect this did not solve the problem.

 

If you turn the key on 2 or 3 times before you try to start it, does it start better? If yes more than likely the pump is bleeding off.

 

Yes, I know for a fact that the fuel pressure builds back up and thus the car will start right up. Strange as it seems, the problem is more noticeable during colder weather, i.e., the pressure will drop to zero overnight, but as the outside temperature rises, the pressure does not drop as much.