Aasalam Walikum,
I have corolla 2016 GLi manual 25k km on odo, it started to give low mileage before it was 11-12 in city. Week earlier it went to 8 kmpl, I changed the plugs to denso Iridium laser ik20, after that it went to 9kmpl, I wasn't satisfied with this average as it's ramdan mostly traffic is low in my area. I changed the mobil to total 5w-30, airfilter, oilfilter and poured abro fuel system cleaner, I have seen no improvements yet it's 100km driven after that. I got it checked it have no errors on the ecu. I really need help how can I improve milage? Is there any way?