huge fuel consumption - FN2

[Vincent_77]

urban fuel consumption 16 - 17 l/100 km which means like 16-17 mpg.
outside urban 10 - 11 l/km which means like 25-28 mpg.
i mention that I rich above figures shifting at 3.5k - 4k, so no vtec.

are all this normal?
to me it looks huge, at the end we talk about 4 cylinders, 2 liters and a NA engine, I don't have V6 or V8.....

the car is from 2007, has 80k km (like 50k miles) and currently i used 5w40 from Castrol.
one month ago i just changed PCV kit but no improvement.
i went in service to test O2 sensor but no errors.

what else I should check?

 

[Loxy]

No, that is definitely excessive.

Check for binding brakes, but failing that it is usually it is the one of the Lambda sensors. It doesn't show a code, but gives a reading far enough out that the ECU throws in a load of fuel all of the time.

 

[Shoonk]

Any modifications?

Otherwise as Loxy said the O2 sensors can cause this when they are on the way out but they don't throw up a code unless they are completely gone.