@Imstallation!
i wonder how could it be possible that this car gave you 50 km on CNG and 10 km on Patrol.
let me give you my observation on this car:
On patrol it gives an average of 15.14 km/L in city while driving on 65 km/hr if you go above it gives 14.22 km/L on A/C.
On CNG if the pressure is above 200psi, the car goes to 110 in City.
the next important thing is the tyre pressure. usually people used to fill 29 Psi averge, but according to manual 30-32 psi must be maintained at all times. this will increase the economy.
Last what company declares that the avg is 15.89 Km/L is true when you must have 35 psi in all 4 general tyres.
Now where is the problem?
1- i think the problem lies in ECM. do visit the chevy dealer and ask him to reset the ECM controller and if you they arent willing, try to go to honda dealers and adjust the ECM software as honda/Santro does have the same device.
Paracha sb,
arent you little bit aggerating, as two of my friends owns GV and club models and they never claims such milages?