Hi so to best explain and get better assistance here it is

I own a 2008 Ford Escape Limited 3.0L V6 4WD.

The issue I am having based on my Fuel Range Indicators is I am getting less KM’s per Tank after every fuel up.

up untill last week I was averaging anywhere between 530 KM’s to 600 KM’s till empty then it dropped to 485 and the fuel up after that said 423 KM’s till empty. Now I am aware this isnt 100% acurate and I make sure the tank is completely full each time, and my fuel consumption itself remains about the same.

I dont drive her aggresive or hard I also knew the likely hood of buying and installing new quality Spark Plugs would not fix the issue but they needed to be changed anyways, The Fuel pump is working just fine as well

I do have a rear exhaust manifold leak had it since I owned it almost a year now has never changed the average KM’s or fuel consumption per tank, yes it will eventually lol it also has a rough idle but only when in drive, Park and Nuetral dont rough idle,

I would be greatful for any suggestions or tips that may correct the issues.

Thanks for your time!

 

I don't know just how much this will help, but,,,,,,,,,,,,,,,
If the o2 sensor is getting an incorrect exhaust reading due to addl air getting into the exhaust it could be read as a lean mixture and thereby reporting that to the vehicle's computer so the computer may be increasing injector pulse width (increasing fuel) to attempt to correct the mixture possibly resulting in increased fuel consumption. Sounds like a real song doesn't it? You might start with getting the exhaust system repaired and see if there is any difference.

 

Its a good place to start thank you for the suggestion I will run a diagnosis for anything out of the ordinary. Fuel consumption is about the same since I bought it, Its the fully loaded Limited model, So it has the feature that tells you how many KM’s till Empty, It drinks the same average 12L/ 100 km’s its just the indicator after I fill up is lower each time, The reading could be from what you described though, Thanks again