8.8kmpl from a MJD with AC on in hardcore city driving is impossible. There is something wrong with your car. Once I drove from Kharghar to Andheri, a distance of roughly 40-45kms which took me about 5 hours due to heavy traffic jam from Bandra to Andheri. I had to idle the car with ACC running for as long as 20-25 minutes many times. The mileage I got was 11kmpl.