U should change the fuel filter immediately, considering quality of Pakistani fuel. It should be changed at 40k kms in any case.
It costs around 4k and it a little hard to change, pump has to come out and filter is part of the whole pump assembly so skill is involved in assembling and disassembling.
My Brother's 300 G is giving 8.5 in city after the service done, all filters, oils etc. when we got it, computer was showing 6.3 per liter, now it varies betweem 8-9.5 with final average of 8.5.
ON motorway he got 12.7 which is remarkable IMO.