I think the pressure developed should increase, and it doesn't. I vote for the pump first, or maybe the filter 'sock' on the inlet inside the tank being clogged.
tom

 

OK... I'll take your advice. I guess its time to rip out the seat.
Can you give a little more detail about the "filter 'sock' on the inlet inside the tank"?
Thanks.

 

The seat bottom pops out with a little maneuvering. I think push the seatbottom rearward, and there are a couple clips at the front that will allow a rod attached to the seat to move upwards, releasing the seat.
Bmulbach noted that the sending unit is held in place with a large plastic nut. [maybe my problems relate to the loose nut behind the wheel... ] He said it was a piece of cake to remove and replace.
I will add that you may need some weird special tools to disconnect the fuel line and vapor line from the sending unit/pump assembly. The snap fittings have to have a tool to compress springy parts to release.
The sock I refer to was a piece of screen that was folded over, with a plastic/rubber fitting on one end that was pushed onto the intake tube of the fuel pump/sender at the bottom. It was there to provide rough filtration for the sediment, rust, and whatever accumulates from getting into the fuel system. They can plug up and cause starvation, but the symptoms would be when there was a long hi-demand situation, such as climbing a hill.
tom

 

I doubt it's your TPS. You can also check the Idle Air Control Valve. I had a buddy who's Explorer was idling rough and had no power. As soon as he changed the IAC it ran just fine

 

OK. Been a rough hot summer here in Texas. Here is where we stand now....
I replaced the fuel pump and that did indeed fix the rough idle and high fuel pressure.
Fuel pressure is now steady at 45in. Much better.

Still had no acceleration. Took it to Midas; they said it needed new cats; so we had three new cats installed.

Still no acceleration. Checked muffler back pressure and there is almost none.

We decided to check the compression. Here is what we found.
1->6 = 240, 240, 240, 140, 190, 160

Then we added a tablespoon of engine oil to 4, 5, and 6. New readings are:

1->6 = 240, 240, 240, 270, 240, 300

Looks like the piston rings are bad.
I am now at the point where I think it is time for a new engine

What do you think?

 

I don't think you need a new engine. There is something else wrong, in my opinion. You have one low cylinder, and a couple that are down a bit, but that still leaves enough to get moving. It has been so long, and I'm lazy, so try running with the MAF disconnected. Check the air cleaner passages, the filter, and make sure the throttle plate opens all the way when you press on the pedal.
I doubt your cats were bad, unless you had back pressure. Did you look inside? If bad, they would have been likely melted. Did they do a back pressure test? Did they check the CAT efficiency? The O2 sensor should have thrown a code if the cats were bad.
When you did the compression test, was it all warmed up with the throttle plate blocked open and the ignition system disabled? The gain in compression is not really believable, to me. Unless this engine was using oil like crazy and putting out blue smoke, I'm just not buying the numbers.
These engines just last too long, even when mal-treated to go at 150k. I think.
You can damage the engine by running without coolant, freezing the block, or letting the oil turn to sludge. If the rings are stuck, try some Seafoam or Rislone type stuff. You can even put either down into the cylinder and let it soak past the rings, though it will take a while. It may free them up.
Really at a loss here. as there should be enough left with the pressures you report to make it still move pretty good. If it really goes for a bit then slows down, unless the pistons are seizing to the cylinder walls, there's something else wrong. Have you checked to see how well it cranks over after you have run it for a while and it loses power? If it is real hard to crank over, you may have scored cylinder walls, or a possible head gasket leak that allows coolant into the combustion chamber.
tom

 

I'm at a loss too. I just don't understand what is happening.

We did the compression check with the engine cold and the intake off; ignition and fuel pump disabled (relays removed).
We were looking at the injectors and decided to do a compression check while we could access the plugs.

Some other items to mention....
We decided on new cats because the front manifold (4,5,6) post cat O2 sensors was melted (but still never threw a code). I have a picture but cannot attach here.

Also, while idling, there are popping noises in the exhaust. What could that be?

Engine starts at the flick of the key whether hot or cold. Starts easily and idles OK, just will not accelerate when you press the pedal.

Could it be the transmission?

 

Subscribed.

 

Starts easily and idles OK, just will not accelerate when you press the pedal.

Does the engine rpm increase in neutral when you open the throttle? You cannot rev the engine too high in neutral, but the rpms should jump without hesitation up to the 3k range.

When you drive and it slows to 10 mph, can you manually select 1 or 2 and get the transmission to down shift?
Does the engine seem starved for fuel? Does it misfire? Does the temp gauge indicate any problem?
Can you run the engine at say 1800 rpms for 5 minutes without problem? I am trying to find out if the engine is binding up or it lacks for fuel or the transmission is failing.
What was it doing, in detail, before all the fixing began? Symptoms? MPG? Stall, hesitation, rough idle, overheat, any and all would help.
tom

 

I just wanted to post the solution to my problem.

First, I wanted to thank everyone who responsed to this thread.
Its great to have your support.

I finally towed the car to two different machanics; neither of which could solve the problem. At least at no cost.

I dreaded it; but, I towed it to the local Ford dealer.
The Ford dealer was actually a pleasant experiance.
They found the problem. I had accidently mixed the plug wires on cylinder 4 & 5.

When I started this ; I will admit I did not label the wires because by looking at the wires to the coil-over; I could see no way to mix them up.
(Still not 100% sure I believe that could happen and that was the problem.)

But for a minimal charge; I'm back on the road and it runs better now then it ever has.

Thanks again for everyone's help.