looking for some help on a problem with a E350 with 460 and single 36 gallon tank, the pump in the tank was bad so replaced with new pump now works but the issue is it wont start unless you dump fule in intake and when it dose start it wont idle wont stay running unless you pump the throtle nonstop however if you continue to play with the throtle it will continue run but rough and like I said wont idle (thinking the pump on the frame rail might not be boosting the presure or working at all, as I am not very on top of this system any thoughts would be great

 

I would start with a new fuel filter on the frame.
Then drop the cap off the single tank fuel reservoir on the frame and clean it out. Replace the the filter in it if it has one. You may have to buy a fuel filter for a 1986 Bronco II to get a new "O" ring.
If that does not do it get a fuel pressure gauge and hook it to the fuel rail.
Start the engine with your way above and see what fuel pressure you have. The engine will not run right under 28psi. Should be 32-40psi.

If you have fuel pressure and still have the problem then see if you have any codes in Computer Memory (CM).

 

I just replaced the sending unit and the pump in the tank as well as the filter the bigger problem is the RV is 6 hrs away, trying to gather a plan to return and nail this problem. If the inline pump is not working would it still run as described above? and what is the easiest approach to test it. Thanks again Doug

 

The in-tank pump puts out about 12psi maximum. The engine will not start or run at all on 12psi pressure.
So if the inline pump is not working at all then no it will not run as described above.
Put a fuel pressure gauge on the fuel rail and ground pin #6 of the self-test plug or short it to pin #2 and turn on the key with the engine not running. You should get about 45psi pressure.

The self-test plug is called the Data Link Connector in the photo below just in front of the battery on the passenger side:




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