HELP w Transfer Flow /fuel sender issue

[Carl-SMB]

2010 E-350 SMB West built with 6.0 diesel
46 gal transfer flow tank

Fuel gauge started acting erratic. Showing half full when full, then swings to empty. Re start another time and it shows 3/4. Not ever accurate with approx 40 gal in tank. Ford diag showed bad fuel sending unit.
The part for this is obsolete and not made in aftermarket nor by Ford.
Ford has no solution.

I noticed that when fuel gauge shows near empty and the warning light comes on that the vehicle throws an error code on scanner P115A-60 Low Fuel Forced Limit Power. Basically when near empty with warning light showing only a few miles till empty (despite being full of fuel) it de fuels and limits power in an effort to conserve fuel.

My local diesel guru is looking to trick the gauge into reading full.

My understanding and experience is that my gauge reads approx 440 miles when I fill it till empty. It also seems to read full when it is full.
This means that the "bottom" of tank must hold the remaining fuel.

That said, if a stock 46 gal tank has stock sender unit, did Sportsmobile West extend the pickup to reach bottom of this tank?

Even if they did, when the gauge shows near empty, you defuel so the last 10 gallons is there but you would have limited power.

Any feedback is welcome.

Thanks!

 

[tskyhi]

I had this issue some years ago. Happened to me, of course, just as I was leaving for a road trip, with the low fuel warning, even though I was nearly full. My first thought was that I'd be screwed figuring it would trigger the defueling mode after so many miles.


Anyway, it's most likely, just an intermittent/dirty connection. There is a plug somewhere on the driver side of the tank that is the connection of the sender into the harness. It lives in a pretty harsh environment. I pulled mine apart and plugged it back in and went on my merry way, with no further issue. I eventually went back and sprayed out the connectors with some CRC QD, to make sure the problem didn't recur.


Good luck.

 

[Carl-SMB]

Ford checked connection and diagnosis was bad sender unit. They claimed connection was fine. A mystery.

Thanks for feedback.

 

[Carl-SMB]

Mechanic tried wiring up another new fuel sending unit without dropping tank just to ensure that is the issue. Worked a few minutes then became erratic again??
Still working on it so if any ideas, please jump in!

thanks