My Aqua 2014 bought 6 months back Grade 4.5 with 43000 Km on ODO was giving me about 16- 20 Km/L on short trips on congested Karachi roads, but now it has come down to 13-15 km/L per trip ( as read from trip meter reading for individual trip) Tyre pressure, oil/Filters & Vent under the back seat are all OK, No error message much like your car, would like to know what you have done to get better mileage?
which air filter and engine oil you used?? I changed the air filter with genuine Denso Airfilter (made in Thailand) . Engine OIL with genuine Honda 0W20. Oil Filter wih geniune TOYOTA OIl filter. And then I just did 4-5 long trips (300 KM per trip) on my car with average speed of 80-100KM/h. Combined average is now 22.5KM/L.
Highway average is 24 & within city average varies according to traffic and weather condition. if high traffic and high temperature avg. drops to 12-16 KM/L, if weather is slightly better and roads are not congested avg. goes upto 20-22 KM/L. and one more thing normally sometimes we leave the car and AC running while we go to shop and some of over Family members sitting in CAR this also drops avg. very quickly.
I am so happy to read this comment, at last I have found someone who know about & uses the "trip average" reading, your " High temp. & High traffic" readings in Pakistan's road conditions are the same as what I am getting. 12-15 Km/L under such condition seem a very economical average