Does anyone know a good write up on how to replace the Water In Fuel sensor.

 

Replaced both fuel filters and the light wont go off?
I just disconnected both batteries for 10mins and hooked them back up and it went off.

 

Ford issued a TSB that covers the problem. Send me a PM with your email address and I will send you a copy.

 

What is the deal with this? I have 40k miles on my truck and the WIF message came on for the first time yesterday. I drained the HFCM last night and it came on again today. So I drained it again tonight. Neither time did water appear to be in the fuel. Will see what happens tomorrow.

 

My wife drove it to DC to visit my mom. 600 mile round trip. I had her fill up at 40 Miles to empty. The light went off after she filled up. It's been 3 days and no light, I think she just got a bad batch of fuel at our local station. I'll be calling them tomorrow. I'm going to change the filters when I return home.

 

The WIF sensor can foul and/or develop corrosion if you get bad fuel (and if you rarely drain from the plug). I open the plug and drain fuel out every oil change. I also drain it into a clear container to be able to fully inspect the fuel quality. I suppose there could have been a bad production lot of them, but from what I have read, the sensor failures appear to be fuel quality related.

 

If you do have to change the sensor which I had to do last year, you must disconnect the 4 fuel lines. I plugged them with dowel pins so they would not leak, then remove 4 bolts in the cover and unplug the sensor wire. My sensor was corroded and the WIF light woulds never go out.

 

I had a problem with my WIF light coming on for no specific reason. I would drain it and it would still come on. I believe when the fuel pump/filter is drained not all of the water comes out. As the vehicle is driven and the small amount of water that remains moves around, it could set off the WIF light and corrode the WIF sensor.

My solution was to remove the drain plug, drill and tap it for 1/8 pipe threads, attach a 90° elbow, insert a 3" piece of brass pipe, attach a female brass coupling and then put in a drain valve. This serves two purposes: it makes draining the fuel pump/filter significantly easier since now all I have to do is reach under the X and open the valve and, since water is heavier then fuel, any water the is in the fuel pump/filter assembly will go into the 3" brass pipe getting it away from the WIF sensor and reducing the potential for WIF sensor corrosion. I normally drain mine about once a month and get about a teaspoon of water out of it. Since installing my modified drain device 3 years ago, I have not had a WIF light come on.

DSMMH

 

My light was constantly on. The fuel heater was shot and corroded which in turn deposited a blue goo on the sensor. I purchased an OEM replacement ($59) off of eBay that did not have the heating element and it came with a new wire harness.