Lets go back to a structured troubleshooting method.

first get the codes out of the computer. look there for any hints.

Test the fuel line pressure again. can it get to 35 psi? should be 35 to 45 psi static, and 30 - 45 when running.

Will it hold pressure when turned off? it should not drop more than 5 psi in 30 seconds.
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Pull the vacumn line on the pressure regulator. Any evidence of fuel there?
if yes, replace
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Lets assume it will not hold pressure. You have a leak. Might be the regulator. see above.

If not the regulator, and you cant find evidence of a line leak. you could have a stuck injector. Use a mechanics stethscope and touch each injector while tunning. You should hear the click-click of the injector firing.

Assuming all injectors are good, then take the inline pump out of the circuit. bypass it. pressurize the system and check for leak down again.

Assuming it STILL will not hold pressure, not the injectors, not the regulator, no leaks you can find externally, then the leak is in the tank.

Pull the tank and the pump, check the hoses for age and cracks. replace those that you can just because. There is a check valve to prevent leak down on the pump assembly. verify that is working.

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I had an issue with one that the rubber hose used to connect the pump to the hard line was cracked (on the assembly in the tank). would not hold pressure, would run but you could feel the power decrease and engine spit and stumble due to lack of fuel. Yours sounds very similar.

 

Well I don't see any leaks what so ever. I have a new tank, new pump in tank, new main pump and new filter and new regulator. I don't have a pressure gage today I am going to borrow it again tomorrow. I found my egr valve totally glogged and in the top part of the pipe I have cleaned it all out but since I have put the new TFI module on I went to set the timing and as soon as I put the spout in it will die and won't start with it in as soon as I take it out it will start and run, but still if I put it in gear and accelarate it will die and won't start.

 

It sounds like you are saying that there is a check valve in the in-tank pump.
Is this what you are saying?
It was my understanding that on these late 80s vans from reading Vol. H that the check valve is in the Hi-Pressure Pump. It also said if it does hold pressure to change the Hi-Pressure pump.

 

Yes. Below is a picture of a fuel sending unit as I know it. My Explorer and my Mustangs have the same basic configuration. I've never seen the unit from a van, so I am assuming that the EFI system is generally the same, either bank or SEFI, (I've worked them both).

Is there a physical difference??

I had the rubber hose split on both cars, so I regularly now replace it when in there. When it split, the vehicl would start, but when you try to use it, there was not the flow of fuel to the engine. It was dumping out the split right back into the tank. The red piece is on the end of the return line. It restricts flow.
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To help with the mustang, I cut a hole in the back to access it easier. 15 minute change outs now. But then it is a race car......
.

 

Well all of that is brand new, i looked it all over and it looks alright of course I won't know until tomorrow when I get a pressure gauge. But I am really starting to wonder if the fuel problem was my real problem, since it is still acting like it did before I started replacing everything. and this with the spout has really got me stumped. And I have plastic fuel lines and I have checked and rechecked and there are no kinks in them and I by-passed the selector valve.

 

Can you tell me what year the photo is from and what year is the Explorer and Mustangs?
Also the check valves in the newer fuel pumps (the ones without the Hi-Pressure pump on the frame) are in the supply line inside the pump not the return.

 

that is a fox body pump assembly. 2000 explorer looked about the same, just taller.

I want to see if I still had a old fuel pump, but the housekeeping staff has thrown all the old ones away. I believe the feed check valve is in the body of the pump (Probst infers that in his Ford EFI book). I seem to recall the small rattle of a check valve. You'd have to have a check on both feed and return to hold the pressure I expect...If I recall. Wish I had an old pump to verify......

 

Well I put the old TFI moduel back on and now when I put the spout in it does like it is suppose to do. But as I go up the road gaining speed it still dies and takes a few minutes to start then you down the road and it dies again as you gain speed. I got 2 codes one was 14 and 31 not sure what they mean on the 14. but this is what I am dealing with now

 

Code 14
Sounds like the Electrical part in the distributor that the TFI Module plugs into may be bad or the plugs and wiring from the TFI Module to the EEC Computer may have a bad connection.

 

Isn't 14 the PIP circuit?
the distributor has a small electronic ignition pickup in it that sends the signal to the computer for firing. An 88 has the EFI system so the PIP signal is used for the ignition system.

You might consider clearing the codes in the computer, and then running the engine and see if they come back. It would just help reconfirm the code. But it seems line the TFI doesn't see the PIP signal.

could be wiring or the sensor. Hopefully not the TFI.
Don't some stores have a tester?

31 is just the egr feedback.

 

Dis you checked the high pressure valve?