1991 Ford E-Series Van dies after warm up

Are you able to keep it running if you feather the throttle when it is warmed up?

Well, it stops abruptly, so there's not really an opportunity to do that, but yeah, it seems to starve on fuel. If driving, and it cuts out, pumping the pedal seems to attempt to keep it running. However, driving it until it pukes, is not very convenient. So, just letting it sit, and idle up to operating temp, it will abruptly shut off (throttle does come down normally as it warms).
Thx,
Ron
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Ron:
If you can allow it to idle until it warms up, then you can check to see if it loses fuel pressure when it happens. Based on the things you replaced and your description, I agree with your diagnosis, fuel related. If you hook up the fuel pressure gauge on the fuel rail, you can watch it from the time you start it until it dies. I think you're right and that is the problem. However, I wouldn't want you to change a fuel pump until you are sure. Here is a how to video that shows how to do it, and it will provide directions. Give it a try and let me know what you find. If you need a fuel pressure gauge, many of the nationally recognized parts stores will lend them to you.

https://www.2carpros.com/car_repair_video/test_fuel_injection_pressure.htm

Let me know what you find.

Joe

Thanks, I ran it again waiting for it to cut out, I noticed that the rpm's seemed to vary a bit. Anyway, I pumped the throttle when it cut out, and kept it going for just a bit before it sputtered on out. This van has three fuel pumps (2 tanks), and this occurs on either tank, so I suspect one of two things tps (due to variations in the rpms) or the frame rail pump is cutting out when it gets warm. It doesn't seem to me a tank pump could push through the rail pump. Your thoughts?
Thx.
Ron
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Pulled the rail pump out of the truck and ran it for twenty minutes, no problem. So I decided to do another test, and ran the tank pump into a gas can, ran a hose out of the gas can to the rail pump, then through pump to the fuel rail. With the rail pump totally out of the electrical circuit, the vehicle ran fine, and did not shut down. Your thoughts?
Thx,
Ron
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