green light auto refusal to fix a car that was not running right since i bought it. still owe 4,800 on car seymour Connecticut

i bought a 2004 madza mpv from green light auto in seymour ct.  paying $ 6000 .00 for the car , i still owe $4800.00 .

the car banged and stalled randomly while driving took it back green light auto, they fixed the banging and claimed to have fixed the stalling problem, charging me $100.00 dollars. it ran well for about two weeks and the stalling started again. green light auto now refuses to fix the car i have had to have it towed more than once  it will randomly stall while driving it will not pass inspection  because of a sensor that is not working. i had it taken to meineke to have it checked they claim it needs $1000.00 worth of work which should have been checked and fixed before selling me the car.

i do not have the money to get the car fixed to running condition and still owe money on the car. i can't sell the car because of the bank loan on the car. but really need it fixed. i need to know what to do.