Fuel MPG problem

[SpeedBumpsHater]

Hi there

EP3 2004 type r
I read post about economy , asked my friends about how many miles you can do on full tank and then I noticed something wrong when I only did about 160 miles on full tank its just impossible no matter that I hit vtec or drive slow there is not much difference.I even tried different fuel , car has pre accident front damage (bumper , cooler) there is no leaking from tank or anywhere for sure anyway I'm pretty sure I could smell it the only mod I've got is K&N air filter any suggestions ? Thanks

 

[Loxy]

It could be the lambda sensor reading incorrectly and the car is compensating by throwing more fuel in.

 

[TomCat]

Does it rattle. If so could need valve clearances