A couple days ago while driving around in my 01 Expedition I noticed a faint thunk-thunk/click-click type of noise in the rear of the truck (I cannot locate it specifically). Always in two's --> Thunk-thunk.
About every 15 seconds +/-

Then this am the truck was just driving along and stalled!
Started back up rough, but got me to my destination.
Headed back home was running fine until I got to a stoplight.

Then ran fine (I floored it out of exaspersation and it accelerated no problems)
So its hit r miss.

Bad Fuel pump?

Or is there a sending unit located back there?

 

Not sure about it being the FP. The noise you describe doesn't really fit. Could be fuel starved, due to obstruction like clogged fuel filter. I think there's also a filter on the pump pick up, as well as in line.

Have you checked to see if any codes are stored? I'd do that first. Listen to make sure you can hear the fuel pump "whirl" (energize) when you turn the key to on. My experience with in tank fuel pumps is that they usually quit altogether and leave you stranded, rather than symptoms you describe. You could check the fuel pressure at the rail. That would give an indication of the pump condition and/or line obstruction.

Check for codes first, though, to make sure you're focusing in the right direction.

 

Thanks. It may very well just be a filter.
I'll check codes to be sure
I did recently run the tank quite low, twice, on a trip.