Fuel filter light comes up what could be the cause?

[Bart F-350]

Three years ago I changed the (still original) fuel filter for a new one, I only drove 200 miles in the beginning of that period.and after that no more.
now the "fuel filter" light in the bottom RH corner of the instrument cluster comes up, if the engine revs over 2000RPM, and I wonder if someone here can tell me what cause that could have?

1989 F-350 7.3L Diesel

 

[mexicanjoe]

You may have a kink in the fuel line causing starvation, and the lift pump is unable to push enough fuel to the injector pump... Carefully examine every stretch of fuel line; both rubber and steel and check for obstructions. Another is to run your tanks somewhat low then use air to blow back into the tank. You may have collapsed showerhead or pick up tube. Hope this helps.

 

[Black dawg]

Switch for that light is a vacuum switch.

 

[Booyah45828]

Either the vac switch is bad, or you have vacuum in the filter.

Plugged filter, bad lift pump, kinked line, failed fsv, plugged showerhead, etc.......

 

[Bart F-350]

Either the vac switch is bad, or you have vacuum in the filter.

Plugged filter, bad lift pump, kinked line, failed fsv, plugged showerhead, etc.......

sorry, Fsv, showerhead?
can you explain those?

 

[Nero]

Fuel selection valve. Another thing it could be is the wire is rubbed somewhere and shorting out.

 

[Clb]

Facett pump?

 

[gandalf]

sorry, Fsv, showerhead?
can you explain those?

The showerhead is the fuel pickup located in each fuel tank. It is therefore at the very beginning of the fuel line. It can get plugged by debris in the tank.

It gets it's name from it's shape. It looks rather like a showerhead.

 

[Old Goat]

sorry, Fsv, showerhead?
can you explain those?

Shower Head is the plastic piece on the bottom of the tube that pulls fuel from the Fuel tank. Has a plastic screen on the bottom of it.

FMFF-1 MTS DIESEL FUEL Sending Unit Funnel Filter Strainer, 3/8" ID Tube

<br /><br /><img border="0" src="https://sep.turbifycdn.com/ty/cdn/yhst-136189531252563/p65warrning.jpg?t=1704229393&" width="320" height="100" /><br /><br /> DIESEL FUEL Sending Unit Funnel Filter Strainer, 3/8" Fits Ford F250, F350, F-Super-Duty Diesel Fuel Sending Units FMSU-5DE, 5DER...

www.gastankdepot.com

FSV: is on the frame of the vehicle on the drivers side on the forward end of the front Fuel Tank.
It is the selector valve that switches between front and rear tank.
The selector switch on the dash board controls the FSV, and switches the Fuel Gauge from one tank to the other.

Here is an example of one off E-bay.

6 Port Fuel Tank Selector Valve For Ford Super Duty F250 F350 Diesel 6C3Z9189A | eBay

Find many great new & used options and get the best deals for 6 Port Fuel Tank Selector Valve For Ford Super Duty F250 F350 Diesel 6C3Z9189A at the best online prices at eBay! Free shipping for many products!

www.ebay.com

Goat

 

[Nero]

Mind you, the light would come on if there was a mechanical issue with the shower head or the fuel selection valve. More often than not its a wiring issue, check to make sure the wire isn't rubbed and grounding out somewhere. Easier than dropping tanks.

 

[catbird7]

If you continue to drive after the light turns on and the engine revs like you just flipped on a nitrous kit, it's likely a blockage / starvation. If the engine continues to run normal its likely a bad switch or bare wire.

 

[Bart F-350]

In that case I'm gonna need Sherlock Holmes!
and start searching, I noticed that since not long the coolant temp gage stopped indicating as well.

 

[Nero]

Oh boy, better pull up a schematic

 

[Rondo]

We just returned from Sacramento to Colorado. About 50 miles from Salt Lake City my light came on. For the last 30 miles I had trouble getting above 60mph. As we pulled into the motel parking space my truck died and wouldn’t restart. In the morning I removed the screen filter I installed before my Holly fuel pump. I cleaned it and I was able to restart and continue home with no problems. I filled up one tank with B20 in Sacramento and I think it loosened a lot of stuff in the tank and line. The filter was black until I cleaned it. Sure glad I installed it at the suggestion of this forum.

 

[Bart F-350]

your filter was Black, as in Black sludge, or a slimey gloob?