Maruti Suzuki — wagon r car -ver bad average of 7.3 kmpl in normal city conditions

Address:

Agra, Uttar Pradesh

Sir, i nalini doneria, owner of wagon r regn no. Up80 da 1962 car purchased the vehicle from ktl pvt ltd, agra in september 2014, since last three months i have been facing a problem in the car of very bad average, the car is giving me a average of 7. 25 km per litre with ac in normal traffic conditions and for 13 kmpl on highway, where as the previous average was 16 kmpl in city and 21 kmpl on average, also note we drive smooth 90 kmpl on highways.
In between problem facing we first got our third free car serviced and send the car thrice to service station of ktl pvt ltd, agra. Every time regular checkups are done and try to show that they have cleared the problems giving vague reasons. I personally feel there is some defect in the piece or some spare has been replaced with the bad part, due to which my car has got damaged. The checkups job card no jc15003705 dtd 21. 05. 15, , job card nojc15004780 dtd02. 06. 15 and on[protected]Where we were not provided any paper and lastly today ie on 17 th june2015.
I request you to please sort my problem or else i will be forced to move to consumers forum for which maruti suzuki india and ktl qill be solely liable to the problem