Worst quality vehicle

I bought a Chevrolet Enjoy 1.3 LT 7 on June 2013. To my surprise vehicle has been giving me trouble from the very first day. It clocked 4000Km now and this is just the 5th month. Vehicle was with their service centres most of the time. It had more than 10 break downs during the period. I had written to Chevrolet India and their local dealer in Kochi to get replacement for the vehicle. But they are not responding to my correspondences and requests.  The vehicle is in totally unreliable condition.

Issues in detail for your understanding I felt the cooling issues (A/c was blowing out hot air only) and noted the engine sound inside the cabin the very moment I got the delivery. Few days later, vehicle started moving in a very low speed (10KMPH). It works normally for the first few kms on cold start. So I have to stop vehicle every 5 kms for 15 minutes to reach somewhere. Their service centre at Kottayam, Kerala claimed that the issue was due to the failure of fuel injection system with the vehicle and they rectified it. Unfortunately the problem (low pulling issues) persisted after covering 500 KM. After 2 days, the service centre delivered the vehicle claiming that the faulty component had been replaced and vehicle was performing well. But after running a very few KM, I saw the engine light glowing accompanied with the pulling issue and the same abnormal sound from engine.  Again with the help of local people I pushed this vehicle to a house nearby and returned back to my hometown in another taxi. The vehicle was sent to service centre as again. After one week, service centre delivered the vehicle again claiming that vehicle is performing well. This cycle happens every time and I don't know what to do.