I’m hoping someone on this form has some insight as to the problem I may be experiencing. I have a 2015 ford f-150 lariat 2wd with the 3.5 EcoBoost. A few weeks ago I noticed my gas gauge would shoot down significantly when I was driving it would go from like 380 miles to 340 in the span of 5 minutes at around 60mph. I took it to a mechanic and they diagnosed a fault fuel pump sensor so I had that replaced and it was okay for a couple weeks but now I’ve gone through almost 200 worth of gas in less than a week . Hoping anyone has any insight as to what may be causing this issue.

 

Since you don't have the diagnostic equip to do some addl checking, if you want to remove a spark plug and It's appearance can tell us a lot.

It can tell us if the engine is really running super rich and consuming way too much fuel or if something else is going on with the fuel gauge system.
The fuel has to be going someplace if you are putting $200 worth of gas in there in one week.
Do you smell any gasoline odors at any time?

 

Thank you for the suggestion, I am bit busy with work during the week but when I get the chance I will pull a spark plug , what would I be looking for looking at the spark plug ? And regarding the gas odors I don’t smell any at any given moment .

 

Just remove any plug, the easiest for you, and tell us the color of the inside part below the threads .

Very simple, if BLACK and fuzzy too much fuel, also means the catalytic converter is working overtime too..

If not black, but a shade of grey, would be considered normal.

It is one thing if the system is providing false info, but completely different if you are actually filling that much fuel.
Just how many miles do you put on the vehicle per week? Are you using regular or premium?