Haven't posted much on here since I went to an15 6.7 from an 11 6.7 and from a 08 6.4 so I thought it was about time to re-awaken myself!
Had an experience with a very annoying sudden noise that came from under the drivers side passenger door on my 15 6.7.
Took Big Blue to work on Monday due to the extreme rain that we had in Central Texas as if I needed to tread water or cut across the median if traffic was stopped, it would be better in Blue than the Sport Trac!
Anyway, lots of water coming home on I35 and all of a sudden a noise from under the cab that sounded like I had just won the lottery! Buzzing, shrill whistle like noise and the longer I drove the louder it became.
Now I have always done my own maintenance and it had only been about 4k since I had change the Fuel Filters. I pulled my 5er to Colorado and back and other towing without issue since the filter change, but this time, with the water on the hiway, I got that noise mentioned above.
I parked Big Blue and let it set till today, as its been wet all week and finally dried enough for me to crawl under it and check out that noise. Started it and had the noise and it was coming from the DFCM or Diesel Fuel Conditioning Module. I thought well it not leaking, no codes, nothing to indicate anything was wrong. I had plenty of power, it seemed. I always have spare filters so I just decided to change them out. Better safe than sorry. Drained the DFCM and cleaned it up, and put it back together with new filter and and also did the one upstairs. Purged the system with 8 key strokes (not 6) and started. All good and in fact quieter than before. The Fuel filter off of the DCFM was pretty well warped and it was pretty dark for only 4k. I always buy fuel at high volume stops, such as J or Pilot so I may have picked up some bad fuel along the way. Also I had not fueled up in a couple of weeks. No water was in the DFCM when I initially drained. The DCFM was tight in fact real tight, but for the life of me, where would that shrill noise with Buzzing that sounded very much like the vacuum pump when you turn on the key sometimes but a LOT louder. Anyway, if someone has an experience like this, first thing I would do is change the filters and make sure all is clean and tight and see if that works. In all my Ford diesels, I have not experience this. Now that I google it, I see that there are some Ford Youtube videos that pertain to noises from the DFCM on 6.7's. Anyway Just a little info that may help someone some day.