Fuel Pressure specs on a 98 4.0 OHV?

[Midwest Dually]

I tried some searching and didn't the specs I was wanting, but on idle, what should the fuel pressure be on a 98 4.0 OHV? And once the engine is run up to 2000 RPM?

In finding the problems with mine, I discovered that on idle I am running 32psi, while maxing out at 38psi.

 

[waskly]

return less run more about 60psi

returned is about 32 psi.

 

[Midwest Dually]

return less run more about 60psi

returned is about 32 psi.

"Return less"? Are meaning with the return line closed off to prevent feedback?

 

[waskly]

"Return less"? Are meaning with the return line closed off to prevent feedback?

around the 98, they changed the fuel delivery to 1 line from two. the two lines allow fuel back to the tank, which is a returned system.

when it has 1 line, its a return less fuel system. 1 supply line.

Contour, Mystique, Cougar (2.5L) 45-60 PSI
Escort/Tracer, Continental 55-85 PSI
Ranger 56-72 PSI
Ranger (Flex Fuel) 47-63 PSI
All Others 30-45 PSI

also note your fuel pressure is good its suppose to be between 30-45. if you have 32 you are good on pressure.

 

[Midwest Dually]

Fair enough! It is the returned system as I do have 2 lines. After all the mud that came out of the fuel filter I was worried. I am not sure the previous owner maintained it like it is supposed to be. I have been getting both the right and left bank lean codes along with misfires, so process of elimination!

 

[windsors03cobra]

The black gas running out of the filter is pretty normal on a 100k mile fuel filter, it is ugly.
The lean code is more than likely a vacuum leak somewhere, unmetered air is being introduced somewhere causing the mixture to be "lean"