Fuel pressure and FPR question

[95exploresport]

http://www.explorerforum.com/forums/showthread.php?t=242731
http://www.explorerforum.com/forums/showthread.php?t=142801
http://www.explorerforum.com/Singleton/web/pages/fuelpr.html

These post has been helpful as I had the same problem of no power going up hills and it falls flat when I floor it. I just checked the fuel pressure and it reads 30 psi ignition on not running, 38 psi engine running. Now the question I have is what should the pressure be? I have read mixed answers on this ranging from 30 psi to 75 psi in the threads above so I need a expert to let me know. *Engine specs below.
Also is my FPR in the tank or on the fuel rail.

1995 Explorer sport 4.0 liter 92,587 miles

 

[swetrid]

It has Fuel pressure regulator is on fuel rail and fuel pressure should be 35-45 psi.

 

[95exploresport]

It has Fuel pressure regulator is on fuel rail and fuel pressure should be 35-45 psi.

Is that running or just with ignition on?

Like I said I am 38 PSI running so that makes it good with what you are saying.

I need more clarity if you could please.

 

[ranger7ltr]

Remember the lack of vacuum with the engine off...

With the engine off there is no vacuum so the fpr has no vacuum to decrease the fuel pressure...The range for this year truck is 30-45 psi...

When you turn the key on, the pump primes itself for a couple of seconds then stops...You may max fuel pressure then it may drop...

Start the engine and you have max vacuum at the fpr at idle and lower fuel pressure...Rev the engine or disconnect the vacuum line from the fpr and the pressure will go up to the max the fpr will allow...

Engine running gives the most accurate readings; the prime test with the key on just tests to see if the pump works and the system is sealed...

 

[95exploresport]

With the engine off there is no vacuum so the fpr has no vacuum to decrease the fuel pressure...The range for this year truck is 30-45 psi...

When you turn the key on, the pump primes itself for a couple of seconds then stops...You may max fuel pressure then it may drop...

Start the engine and you have max vacuum at the fpr at idle and lower fuel pressure...Rev the engine or disconnect the vacuum line from the fpr and the pressure will go up to the max the fpr will allow...

Engine running gives the most accurate readings; the prime test with the key on just tests to see if the pump works and the system is sealed...

Got-it!
Thank-you!