Fuel Filter Light - Diesel Forum

93 f 350 · 11-04-2009, 06:41 PM

Hello all ,i was hauling somewhat heavy the other day ,and the fuel filter light
on my truck stayed on whenever i stayed on the pedal ,when i released the pedal it go off ,what does that indicate also how do i check the heater on the filter (fuses wiring etc )and can i cap the return valve on the filter that goes to #1 inj.to increase pres.,i have an electric inline pump and runs at
3 to 4 psi idling
thanks for any info

chuckster57 · 11-04-2009, 06:49 PM

The "fuel filter" light is activated by pressure and it normaly indicates a plugged or clogged filter. Mine did it about a week after I bought the truck and filled both tanks. Took a 200 mile trip and it came on about 1/2 way home. I took the filter off and found a bunch of junk in it. Changed it and it hasn't cme back on since.

Greenie · 11-04-2009, 07:53 PM

The fuel heater is too small and poorly placed to be of any use. It's very expensive too. As long as it's not leaking I'd leave it alone.

rsr911 · 11-04-2009, 08:57 PM

I run blends in my van and when I was first experimenting I had to change a lot of filters before I got my pre-filtering down cold. The light is coming on either because the filter is partially clogged or your electric pump is dying a slow death. What kind of pump is it? I'd replace the filter for good measure anyway though.