Sir
I recommend service your throttle body, injectors, check the valve clearance, spark plugs, ignition, air filter, fuel filter and fuel lines for any impurities.
In a worst traffic jam my 05 EXI PROSMATEC gives me not below 7 Km, normal is 9 km, 11 km with a very gentle foot and good road conditions with A/C.
Averaged 13 km once on highway without A/C, route to Kurley lake.
Have you done a 50K or 100K check on your car from any Honda or other workshop?
regards