The car is fine and reliable and is regularly used on long routes without an issues the only gripe currently is the poor fuel efficiency. Honestly speaking agar 14 km/l b ker laiti hai with AC on highway, it will be acceptable.
So the car's been with us since 2005. The engine assembly has been changed once at around 150-160k kms, i think not sure. It was changed after the head gasket gave way and engine overheated. The head was machined twice before going for the assembly change. Car's current reading is 222k km.
With regards to the engine's performance I believe it is fine. It goes up to 175 km/h without air conditioning and 160 km/h with AC switched on. Acceleration however is somewhat weak, I don't have exact figures, I presume for 0-100 it's about 15-16 sec. I'll update this with exact figures when I drive the car again.
The mileage is the main concern currently. Injectors, plugs, throttle service, fuel filter, tappet adjustment has all been done fairly recently. The mileage is calculated with the top up method so is accurate and is based on countless tank top ups. The car gives 8 km/l without AC in city. On semi highway (Islamabad Highway) it managed 9.5 km/l without AC with very light foot i.e 80km/h @2k rpm. On motorway at a constant 120 km/h from Faisalabad to Islamabad it managed 11.7 km/l with AC. It used to do ~13 km/l with AC.
The car is driven normally like any mature person would drive, no hypermiling but usually driven in a calm manner. A lot of time has been spent in trying to improve this mileage. However, I am open to any suggestion you guys might have. Transmission feels fine once in a while it gives a jerk in the first gear, but it is very rare and not bothersome. But since the transmission is old now it might be the reason for the poor mileage.
Is there any engine that can give 15 km/l AC on highway with an automatic transmission? Highway speeds are going to be 110 km/h on GT Road and 120 km/h on Motorway. I am interested in D15b Vtec 3 stage and it's not because every honda fan boy get's this but because the car is driven calmly at lower stage it might deliver good fuel efficiency and if sometimes I get to drive it, I can enjoy it when required However, if there are anyother engines that I should look at please let me know. Budget is not a constraint, but the requirements above are.
Should I opt for the CVT transmission or can the normal transmission get 15 km/l on highway in which case overspending on CVT will be a moot point.
Looking forward to your help.