Make sure you DOCUMENT this current effort to fix. Arguably it is a warranty or it is work being done under warranty. Further, if they did not post the buyer's guide you should have a warranty, since they cannot properly disclaim. Try Mike Flinn in GA.
It sounds like you have a claim. Check your paperwork for a limited warranty (30 or 60 days is typical). If not, the dealer's initial comments about the car and subsequent promise to fix the engine problem are probably actionable. I recommend contacting a consumer protection attorney ASAP. Also, those cases can require the defendant to pay your attorney's fees. The problem is that the dealer may not have a lot of cash or insurance to cover losses.
General advice based on limited facts. No attorney-client relationship created.
Can you cancel? Maybe but you'll likely need a lawyer's help. There is a used car lemon law in Hawaii, Massachusetts, Minnesota, New Jersey, New York, and Rhode Island, but not in Georgia. So that means you have to look at your sales paperwork first. If there is no warranty or guarantee there, then you look at the oral representations that were made and ask if you are the victim of fraud. There is a long technical definition for fraud in each state but basically it is a lie that costs you money. If your purchase was “as is” then that is what the dealer will argue to avoid doing anything for you. Practically speaking, “as is” isn’t always legally as is, even though every car dealer wants you to think so. In most states, your legal rights in a used car sale are mostly determined by the paperwork that you sign, what you were told by the dealer, and if the dealer hid anything serious about the vehicle from you. But even in an “as is” sale you might get some legal rights anyway, even if you thought you didn’t. And besides that, if the seller hid something from you that they knew and also knew you would want to know about before committing to the purchase, then that can be fraud - regardless of any “as is” sales attempt. Also, in some states an oral representation by the seller may over-ride a written disclaimer of warranties. Also there’s a federal law that requires all car dealers to post on the window of all used cars they are selling a special “Buyer Guide” form (it’s often called a Used Car Window Sticker) that discloses your warranty rights. Many small lot car dealers don’t comply with the law. If they don’t, then you may end up with a warranty after all and you may even have the right to cancel the sale. The back side of the form has to be completely filled out and many car lots, big and small, fail to do that too and that can also trigger your right to cancel the deal. You can see what the Buyer Guide form looks like on this web site page: http://tinyurl.com/8wv7tvv. Once you have already spent your money, it's not too late to have an independent repair shop inspect it and tell you what they think, but the best time is before you put down your hard earned money. If less than a few thousand dollars is involved, you may want to go to Small Claims Court on your own instead of getting an attorney. To find out what your rights are in your state, you need to talk to a local Consumer Law attorney who deals with car sales fraud, like Mike Flinn or one of the others in GA. You can get their contact info at a Free Online 50 State National List of Consumer Law Lawyers www.USLemonLawyers.com (lawyers don’t pay to get listed here and most of them are members of the only national association for Consumer Law lawyers, NACA.net). You can also look for one here on Avvo under the Find a Lawyer tab. Or you can call your local attorney's Bar Association and ask for a referral to a Consumer Law attorney near you. But act quickly because for every legal right you have, there is only a limited amount of time to actually file a lawsuit in court or your rights expire (it's called the statute of limitations), so don't waste your time getting to a Consumer Law attorney and finding out what your rights are. If this answer was helpful, please give a “Vote UP” review below. And be sure to mark your Best Answer so Avvo lawyers know we are doing a good job. Thanks for asking and Good Luck. Ron Burdge, www.CarSalesFraud.com
What a Used Car Buyer Guide Looks like - Click Here
What Is Fraud? Click Here to Find out
Did a Business Treat You Unfairly? See What Your Udap Rights Are to Protect Yourself, Click Here
Learn the 3 Kinds of Fraud, Click Here
Free Online 50 State List of Consumer Law Lawyers, Click Here
How Can You Avoid Buying a Lemon Used Car? Click Here to Find out
This answer is for general purposes only and does not establish an attorney-client relationship. The law in your state may differ and your best answer will always come from a local attorney that you meet with privately. For a Free Online 50 State National List of Consumer Law Lawyers, click on this link (http://tinyurl.com/79ku5jx) and find one near you