Purchased a used vehicle

I bought my first vehicle on March 30, 2013 from M. Auto Center West for my 20th birthday and after 3 days the engine light went on. I had it towed back to M Auto West. I then called them and brought it back several times. Not only was I not given a receipt for any work being done, nothing was fixed. I then had a reputable mechanic check it. It was found to need a new radiator, fan clutch, head light, license plate light, tune up, oil change, several hoses,etc. $950.00 worth of work. It was a unsafe car. They denied that I brought the car back in 3 days in which I have a receipt from my towing company. They also claimed that I didn't contact them until 3 1/2 months after purchase, which is untrue. A complaint was made to Better Business Bureau and California Department of Motor Vehicles until this matter is resolved.