I own a 2008 Honda Civic 1.8 Prosmatec. The car is now driven 26,000KM. Since about 4 months, I have noted that the average I get per tank of fuel has been quite low as compared to when the car was new and also as compared to my 2001 Corolla (1.6). On 36 liters of fuel (Rs. 2500), I got only 350km which is almost 10km per liter. I have gotten previous readings which were about 310-320km. My Corolla on the other hand gets 450km on the same quantity of fuel.
I am a daily commuter from Pindi to Islamabad which means that I use Kashmir highway and there is not stop and go traffic. Also, I have not been pushing the throttle at all recently. All my shifts are from 2500-3000k rpm.
I am wondering why I am facing this problem and if other owners of this car are also facing such problems. It has come to my attention that one reason this might happen is due to a blocked catalytic converter. Does removing it solve this problem and save money at the pump? Also, some people say that this new civic is meant to be driven on hi-octane (which is regular petrol in foreign countries).
I will highly appreciate if some members who actually own this vehicle can share their experiences. Thanks.