Product: Vehicle loan or lease

Hello, I put a down payment of {$4900.00} plus a payment fee to use my debit card for this vehicle. My grandfather assisted me by co-signing for this car ( elderly ) and was told that documents had to be signed electronically, so it took a while for him to sign. He had to keep asking questions during the process. We bought this car on XX/XX/XXXX late evening around XXXX. Weve been having issues with this vehicle from the time we drove off the lot. We went back to the dealership on Monday XX/XX/XXXX because the tire sensor was on. I asked the sales associate why was the light on and he clearly stated Oh the tire sensor is dead on that side it wasnt nothing major and probably will cost you just {$100.00} to get it fix that made me think what else are they lying about this car and something else major wrong as well. Four days later going to make a deposit at the bank 11 min from my home the car completely broke down at the bank. A mechanic close by said it was the fuel pump just by hearing the car not turn over or crank. Called the dealer and they were not willing to do a good faith repair at all and it was only 6 days having the car. The General manager got in the phone stated if its a minor fix he will help cover if not then we had to cover it. He advised to take it to his mechanic XXXXXXXX XXXX XXXX XXXX XXXX XXXX XXXX. XXXX The mechanic was unwilling to provide us with a complete diagnostic print out and just did a printout price to fix the fuel pump. XXXX the mechanic stated it was a minor fix and the dealership should be able to do a good faith repair. We went to the dealership in person and the general manager stated it was a major fix and that he wouldnt be able to help pay out of his pocket {$810.00} I asked pay for the labor {$150.00} would he cover the rest. He said yes, and that he wouldnt be able to help again at all if theres anything else wrong with the car. His mechanic XXXX  who fix and work on all the dealership cars, fixed it the same day. Fast forward to today I had an appointment to get a a real diagnostic check and was advised that the car sold with a major mechanical issue dealing with the engine and to take that car back since weve had so many problems and its only been XXXX weeks. The car started running hot on yesterday and broke down so I had to park it in a parking lot and leave the car. This was a terrible mistake buying this car from this dealership. Please help us unwind this deal weve spent too much money. 
This the email sent to the lender Westlake Financial along with XXXX different diagnostic tests done to this vehicle on XXXX XXXX again on XX/XX/XXXX and XXXX XXXX. The lender will not and hasnt responded. The dealer ship is XXXX XXXX XXXX in XXXX, SC XXXX that sold the car. I called the lender Westlake financial several times on recorded call and their response was a fuel pump was not a major issue or problem and they denied the claim. I also sent in all three diagnostic reports where it shows a blown head gasket. also sent to the same day to their Fraud audit team, dealership compliance team and their customer service department, they refuse to send any email, letter or phone call with a denial letter or any response at all. I called today and still no kind of response, letter the lender is being unwilling to do any action as I was promised on XX/XX/XXXX via phone call, if I sent in all diagnostic information within the next week and I did on XX/XX/XXXX, XX/XX/XXXX, XX/XX/XXXX again today. Ive made calls every week from XX/XX/XXXX until today XX/XX/XXXX no cooperation from this lender in unwinding the deal or speaking to the direct department on why this deal can not be unwinded. I also submitted a complaint to the SC XXXX for a dealership complaint on XX/XX/XXXX. 
Here is another email sent to XXXX XXXX sent on XX/XX/XXXX Hello, Here is the invoice where I paid {$140.00} to the dealerships mechanic ( XXXX ) at IDEAL AUTO REPAIR AND TOWING XXXX was unwilling to give me a copy of the total diagnostic of the car, he stated we just need the fuel pump fixed and the invoice should be good enough. This made me feel very uncomfortable. The day of my purchase, I was looking to get different car XXXX XXXX RT off their lot but was told I needed at least {$10000.00} so they pulled the XXXX to the front and offered that car instead. Now it feels like they wanted to get rid of this car and even offered it at a lower price, this has been a big headache and very exhausting because of all the issues ; problems with this car and its only been XXXX weeks. My grandfather is furious and upset feeling like the dealership got over on XXXX because hes elderly and wheelchair bound. The car ran super hot yesterday and broke down on me near XXXX XXXX XXXX in XXXX, SC. I parked it at a doctors office and havent had it towed as of yet. XXXX asking you to please help me unwind this deal, this wasnt a good sale to me and my grandfather at all, its has been very frustrating for the both of us. Please excuse any or all grammatical mistakes and errors as this was sent from my XXXX