Tata Motor - Defective fuel pump

I have purchased Tata tigor xt in ****.
After one year it start giving problem.
On long route the car stops accelerating properly and starts jerking.
I complained about this in sagar motors during the service time , they told me that they solved the problem.
But again on long drive the car starts jerking and not accelerating properly, i again told them at the time of service ,
But not get positive response.
Now the problem is still happening , and now they are telling me to change the fuel pump .
But now the car is out of warrenty ,
But my point is that i have complaint about it when my car was in Warrenty.
Please i request Tata motors to change my car fuel pump.
I also check about this problem on internet , and i get to know that most of the tigor and taigo are facing this problem. Please change it as it is manufacturing defect and i had complaint it during warrenty period.