You will need to have another mechanic to look at the vehicle and tell you what is wrong and what it will take to fix it, and how much it will cost. You then sue the first mechanic in small claims court for that amount and subpoena the mechanic you hired to review the car to got to court with you.
Mike is right about getting an estimate and then going after the first mechanic in court, perhaps small claims court if the repair cost is not too much. When you take a car to a repair shop for them to do any kind of work on your car, you have the right to expect the work will be done right. And unless they use special language to avoid giving you a warranty, in most states you automatically get a warranty that they are going to do the work in a "good workmanlike manner." That basically requires that they do the repair or service work right. If they don't, then you have a right to recover damages for what they do wrong or the damage they cause. But you have to be able to prove that the reason for your new problems is something that the repair shop did or did not do. In other words, you have to be able to show that it was fault of the repair shop. Once you have asked the first repair shop to fix it and they won’t do it under their own warranty, then you have the right to get it fixed somewhere else and then hold the first repair shop liable for the repair cost. If the cost is less than a thousand dollars or so, you may be able to sue the shop in your local small claims court without needing a lawyer. Doing the repair work badly may also violate other consumer protection laws in your state. Because the law is different in each state you need to talk to a local Consumer Law attorney to find out what your legal rights are for sure and get some advice on how to proceed in your local small claims court or see if you need an attorney. Call your local attorney's Bar Association and ask for a referral to a Consumer Law attorney near you or you can go to this web site page for a Free Online 50 State National List of Consumer Law Lawyers (http://www.ohiolemonlaw.com/ocll-site/ocll-locate_local.shtml) and find one near you (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). 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 check the box below.