Rep Power: 0

Hey guys ,happy owner of an Fk17 1.4 here ,i bought this car almost a year back ,and since the start i always had a fuel consumption problem it takes 7 to 8 L / 100 km and i think it's excessive for this model , what i did to try to resolve the issue
-New tires and balanced them
-Cleaned fuel pump
-cleaned the catalyzer
So after all that the issue stayed and got a Diag tool to dig deeper
What i see is that on idle (btw i have a rough idle) the stft and ltft stays at around 1 so everything seems normal
If i go at around 70km or less with 1,5 to 2k rpm it just stays normal and the fuel consumption seems normal
But if cruise on the highway at more speed 90 or 100 km /h or more the stft jumps instantly to 1,47 and ltft just keeps going higher to 1.30 more or less and i saw that especially when this happens the AF ratio shows 27-28 wich indicates a lean condition but all of this happens while i'm on throttle cruising and the instant fuel reader on the dashboard shows 10 L/ 100 km at the same time

My guess is either one of the sensors is a big liar or maybe i have a vaccum leak ? I wanted to share this problem with you guys ,what do you think ?

 
Rep Power: 221

Can check for a vac leak by spraying brake or carb clean around the intake to see if the idle changes. Primary o2 sensor might be on the way out.

 
Rep Power: 0

Tried to blow air with smoke inside to see if i have any vaccum leaks ,found nothing
I ordered a new AF sensor ,will re try afer i have it and keep u guys updated