Lost fuel avg

Not to be a smart ### or anything but you say its a 2015 truck? Have you taken it to your local dealer for thier thoughts? Don't you have warranty left on it? I know the warrantees aren't as good as they used to be but how much money are you losing with this bad fuel mileage? You posted in Dec and its the end of Feb now. I'm not crazy about spending big bucks at the dealership either buut...

 

It sounds like air getting into the fuel, have you tried new fuel filter? It's worth a shot.

 

If you had the Overhead Ran, that would have been an ideal time to spin on a new fuel filter and examine the lines to ensure your not sucking air in some where.

 

Have you done the rawze egr clean out? It may be all carboned up. Including a plugged dpf and sensors all clogged up with soot.

 

OK here is a question for you.

Does your fuel filter look something like this?

 

You won't find a thing wrong.

Here is what I think is going on.

When you had the filter change, they don't normally change the pre-filter - like the picture in my post.

They ignore them and you have to be specific.

These pre-filters have a Water-in-fuel sensor that lights up a light on the dash, sometimes it can be tied into the fuel filter light (forget how that is done but it can be done).

SO here is the thing.

When you get the thing completely full with a little bubble on the top, it is time to change the filter in that unit.

ALSO you have to drain the water out of the filter bottom (they usually have a ball valve on the bottom of the unit).

The water is the real issue.

Get a bucket, five gallon size because this become messy. Open the top of the filter (the black plug) and then open the valve on the bottom, let it drain a little bit, you can tell the water from the fuel (or should) and then shut the valve, then close the top (the black plug) to seal it back up.

You should see a difference.

AND get the filter changed.

By the way, watch who ever changes the filter. make sure they use the right wrench (they make a special wrench for this) and if they don't, have someone else do it. I would also get that wrench and a couple filters to keep in the truck for the future.