* Implied Warranty of Merchantability: Most jurisdictions have laws implying a warranty of merchantability when you buy a used car. This means the car should be fit for its ordinary purpose (driving) for a reasonable time. A major engine failure within six months strongly suggests a breach of this implied warranty, especially if the undisclosed prior engine work was significant. The fact they didn't disclose the work is a key piece of evidence.
* Fraudulent Misrepresentation: If the dealership actively concealed the engine work (e.g., by cleaning up the engine compartment to hide repairs or making false statements about its history), you might have a claim for fraudulent misrepresentation. This is a stronger claim than a simple breach of warranty, as it involves intentional deception. You'll need proof of their knowledge and intent to deceive.
* Lemon Laws (Possibly): Lemon laws typically apply to new cars, but some jurisdictions might extend protection to used cars under certain conditions. However, lemon laws often have specific requirements (like multiple repair attempts) which might not apply in this situation where the failure is immediate and related to pre-existing issues.
* State-Specific Laws: Consumer protection laws vary from state to state. Some states offer stronger protections for used car buyers than others. You need to research the laws in your specific jurisdiction.
What you should do:
1. Gather Evidence: Collect all documentation related to the purchase, including the sales contract, any warranties given, and any maintenance records you can obtain. Document all communication with the dealership. Take photos and videos of the engine and any related problems.
2. Contact the Dealership: Explain the situation and provide your evidence. See if they're willing to repair or replace the engine under a good faith effort, even without a formal legal action.
3. Consult with a Lawyer: An attorney specializing in consumer protection or lemon law can assess your specific situation, determine your rights under your state's laws, and advise you on the best course of action. They can help you build a stronger case and negotiate with the dealership or file a lawsuit if necessary.
4. Avoid Further Repairs (Possibly): Before authorizing any repairs yourself, consult with a lawyer. Unnecessary repairs could weaken your case.
In short: Don't give up. The undisclosed prior engine work significantly weakens the dealership's position. Seeking legal counsel is strongly recommended to explore your options and determine the best way to resolve this issue.