99 Ranger 4.0 - Fuel Pressure problem

Having problem with my 99 Ranger 4.0, rough idle, rough starting. Bought it last summer with 105,000 miles on it with unknown service past Problem is
sporadic sometimes idle is good and other times it's so rough that the truck dies while backing out the drive (usually it's the worse when the engine is cold). I have replaced MAF, idle control valve, plugs, plug wires and the ignition coil; all with really no effect expect after replacing the MAF, the truck has much more power but idle is sporadic with roughness.
In thinking back about the idle problem and having poor gas mileage, I started thinking more on line of fuel issues; I bought a fuel pressure tester and checked it. To my shock the fuel pressure is 65 lbs at idle, as I understand according to my Chilton's book the pressure should be more like 30 lbs at idle. Would I be correct to replace the fuel pressure regulator? to my understanding the regulator on the 99 is a non-returning regulator so a plugged return line wouldn't be the issue.
Any thoughts on this?
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throttle position sensor.

it
truck
is
the
as
like
regulator?
so
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His TPS doesn't have a damn thing to do with fuel pressure. He's on the right track with the fuel pressure regulator. Bob

is
the
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wrote:

The fuel pressure regulator is what you need assuming you have made sure the vacuum hose is properly connected. If it does not respond to vacuum at the regulator, then the regulator is bad. Around 35-38 is normal at idle. It can go lower or higher depending on vacuum. I have played with a hand pump and watched the vary between 20 and 45 psi. 65 is WAY too high
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You guy's are missing the boat. The fuel system on this vehicle does not have a external mounted regulator and return line; i.e. a returnless fuel system. There are no vacuum lines on the regulator. The fuel pressure specifications are 56-72 psi. The basic engine needs to be checked, ( compression test hot and cold ) before any electronic diagnosis is attempted. It also needs to be questioned of the actual idle quality, does it truly idle rough or is the idle quality the same as the same year vehicle?

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Dammit Moats, you are right again. Bob

Bought it

is
truck
engine is

the
MAF, the

idle, as

like
regulator?
regulator so

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Sorry........

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That's okay Tom, I've kind of come to expect that from you. Bob

Problem
the
and
mileage, I

pressure
more
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Well that's ok as long as you don't expect too much. I aint perfect.

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On Sun, 11 Apr 2004 16:24:39 -0400, "Thomas Moats"

I think I'll just tuck my toolbox between my legs and disappear into the woodwork.

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it
truck
is
the
as
like
regulator?
so
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On Fri, 16 Apr 2004 19:00:15 -0400, "Thomas Moats"

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wrote:

have
cold )

questioned
the
And ya know? She still does.
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I have checked the cylinder compression and all is well; After more research, there is a common issue of bad intake gaskets with the Ford 4.0's.
I plan to replace the upper & lower intake gaskets this coming weekend and go from there....
Yes the fuel pressure is in the right range, the Chiltons book does not describe the proper pressure and is wrong (at least the one I have) so my fuel pressure is not out of range as first suspected.

it
truck
is
the
as
like
regulator?
so
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