Fuel pump pressure

Does anyone knows what the range of the fuel pump pressure for the expedition 2009 ? And how many psi below the rang can be accepted ?

hussam, you should see 40-50 psig on the fuel rail with the key in the RUN position and the engine not running. Once you start the motor, it will drop to 30-40 psig. In both cases, the pressure should be up near the high end of the range. Going outside of this range is considered a bad reading.

55-60 psi

are you sure cause one mechanic told me for 2009 it should be between 55-60 psi. My fuel pump shows 50 psi after starting the engine.

are you having a drivability issue? Why are you concerned with fuel pressure? I wouldn't think on its own I would worry about a 5psi variation.

I would ask someone who services the later model expys (specifically your 2009) as ford has gone from a return style fuel sytem to a mechanical returnless system and believe now an electronic returnless system. Not to mention the new direct cylinder injection fuel systems. I believe but not sure you may have an electronic returnless fuel system.

Just not sure there is many in the forum who has serviced the later models yet.
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1st gen expys have a return style fuel system and the specs out of my 2000 expy service manual read as follows:

Engine Running kPa (psi) 193-310 (28-45)
Key On Engine Off kPa (psi) 242-310 (35-45)

When tuning the earlier ford return style fuel systems I have always set fuel pressure between 39-42 psi with vacuum line disconnected from regulator. Not as concerned with fuel pressure at idle in modified vehicles because because many times vacuum is less than stock..

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According to my Haynes manual which I put less faith in because it is more generic, 2005 and later (book only goes to 2009) returnless systems fuel pressure at idle is 35-70 psi. Quite a range there?!


For any vehicle I own and plan to maintain (or modify) I always get a service manual for it. They are invaluable. I think you can even download them now via the web.

Tom you are correct, it is an electronic return less fuel system and there are variable fuel pressures depending on demands from the PCM. Not exactly sure what the variables are.