I am very sorry to hear this;
there are a few different issues;
first, since a car that is not sold as is comes with an Implied warranty of merchantability- this means that the car will do what it should (ie be driven). If the car's defects are so substantial that this is not possible, then one can sue for breach of contract (the car that was delivered was not operable in a manner that a reasonable person would suspect).
Second, an express warranty does not give the seller unlimited attempts to repair the car. Rather, the seller is given "a reasonable number of opportunities to repair" - https://www.consumer.ftc.gov/articles/0055-buying-used-car#warranties. Failing to provide a working vehicle after a reasonable opportunity to repair (generally 3-5 visits) allows the buyer to void the contract.
Additionally, a certified car attests that the car is of a certain quality; if the car is not of that quality, that will also support a claim for breach.
One can first attempt to negotiate to void the contract (return the vehicle, return monies paid, deducting for "reasonable use" -typically based on miles). Failing that, one would need to pursue an action in court. An itemized statement of repairs, along with a third party professional analysis, would help prove that the car did not meet reasonable consumer expectations.
In FL, small claims is limited to amounts less than $5,000 (http://www.flcourts.org/resources-and-services/family-courts/family-law-self-help-information/small-claims.stml) so one would need to pursue it in regular civil court, should negotiations be unsuccessful.
A complaint can also be filed here:
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Information provided is for educational purposes only. Consultation with a personal attorney is always recommended so your particular facts may be considered. Thank you and take care.