DFCM draining...
Fleet Mechanic
Joined: Jun 2009
Posts: 1,346
Likes: 4
From: Connecticut
For the guys that check for water more frequently than monthly...I'm assuming the reason is obvious (easy check to avoid a disaster) however isn't the WIF sensor located in the DFCM? If the sensor is working properly wouldn't it "sense" any small amount of water? Or does it take more to trip it? Of course if the sensor fails you'd find out the hard way. A redundant sensor would make sense.
I guess I'm wondering if the sensor is designed to tell you to drain the DFCM or is it to tell you "your in trouble". I never want to see my WIF light come on because then the PCM will always remember it. Imagine 30K miles later you have a HP pump fail and the dealer plugs in the diagnostics and says "ah ha!" you had a WIF sensor come on two years ago which means you in fact had water in the fuel which means you're warranty is denied
I guess I'm wondering if the sensor is designed to tell you to drain the DFCM or is it to tell you "your in trouble". I never want to see my WIF light come on because then the PCM will always remember it. Imagine 30K miles later you have a HP pump fail and the dealer plugs in the diagnostics and says "ah ha!" you had a WIF sensor come on two years ago which means you in fact had water in the fuel which means you're warranty is denied
Im curious of the answer to your first question.Shouldnt the sensor kick on if you find water in drain? Wonder how much it takes to alert the sensor.
Laughing Gas
Joined: Jul 2010
Posts: 1,155
Likes: 31
From: Idaho
WIF
I have not seen any water in diesel in 5 years. The lights will comes on when water rises and touches the sensor. The sensor is not at the very bottom of the fuel bowl.
As far as what to do if you find water in fuel. I would drop fuel from the tank and refill with fresh diesel. It also really depends on how much and how fast it is collecting. I would like a better sensor on the tank to detect water. There has to be a better way.
As far as what to do if you find water in fuel. I would drop fuel from the tank and refill with fresh diesel. It also really depends on how much and how fast it is collecting. I would like a better sensor on the tank to detect water. There has to be a better way.
Post Fiend
Joined: Oct 2002
Posts: 11,314
Likes: 4
Fifth ford diesel truck and I've never seen water....
NOW on one of my Excursion (2003 or 05???) I didn't need to see it as the truck died and the dealer found like 50% water... (in the jar)
Went after the station since I knew if I got it, others did too, but of course they said "Not us" !!!!
Glad I had gotten into the habit of saving the last few diesel receipts,
so State Farm paid for it all > $5000 IIRC, including my tank of diesel... then went after the station...
I guess I wasn't the only one that had an issue as that station closed down a bit later
NOW on one of my Excursion (2003 or 05???) I didn't need to see it as the truck died and the dealer found like 50% water... (in the jar)
Went after the station since I knew if I got it, others did too, but of course they said "Not us" !!!!
Glad I had gotten into the habit of saving the last few diesel receipts,
so State Farm paid for it all > $5000 IIRC, including my tank of diesel... then went after the station...
I guess I wasn't the only one that had an issue as that station closed down a bit later
Postmaster
Joined: Sep 2006
Posts: 2,598
Likes: 5
From: Maryland
If you look at the bottom of the filter housing, you can see the water reservoir. It looks to me like it holds at least 6-8 ounces before the water will trigger the sensor. It does seem like a reasonable idea to have some sort of WIF sensor in the fuel tank.
Lead Driver
Joined: Jan 2010
Posts: 6,600
Likes: 84
Technically it's been checked when you've changed fuel filters but you might want to add that to your monthly list!
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Lead Driver
Joined: Sep 2006
Posts: 5,665
Likes: 164
From: Cartersville, Ga
I would like to see them put a piece of metal after the DFCM in a sight glass so you can see if it is acquiring rust. That way you know where you stand because if it starts acquiring rust you could maybe change your fueling habits before it's too late.
Senior User
Joined: Nov 2013
Posts: 163
Likes: 0
From: Albany NY
For something that has to be checked monthly...What a Pain in the A$$
It's really pathetic to watch my 78 year old neighbor cursing while climbing out from under his 2014 truck (from which he was laying on card board over the snow), with diesel all over his hands.
He has the same issue I have on my 2012. There you are, holding your mason jar under the DFCM drain port as you slowly turn out your yellow ****, patiently waiting for diesel to enter your jar at which point you turn your yellow **** back in and never spill a drop...right? Wrong! the diesel flows from the yellow handle all over your hand before it flow from the spout it was designed for.
I have read that others don't have this problem because they don't turn the handle that far out. He nor I will not get any flow from the drain port until we open the valve to the point it leaks from the ****.
It's really pathetic to watch my 78 year old neighbor cursing while climbing out from under his 2014 truck (from which he was laying on card board over the snow), with diesel all over his hands.
He has the same issue I have on my 2012. There you are, holding your mason jar under the DFCM drain port as you slowly turn out your yellow ****, patiently waiting for diesel to enter your jar at which point you turn your yellow **** back in and never spill a drop...right? Wrong! the diesel flows from the yellow handle all over your hand before it flow from the spout it was designed for.
I have read that others don't have this problem because they don't turn the handle that far out. He nor I will not get any flow from the drain port until we open the valve to the point it leaks from the ****.
