I know in NC it has to be the same exact failure 3 times with in an 18 month time frame. There is no limit to shop time. Now here is where it gets tricky. If the motor is running rough, and they do a tune up, spark plugs, the problem comes back still rough this time they do a coil, then still rough now they change injectors, still rough so they install another set of plugs. You only have two of the same problem, spark plugs. The dealers act stupid on this but know the law inside and out. Make sure that on any work order that ALL and EVERY Problem is written down. Keep sharp notes, times, miles, and anyother related problem that you find. Now some states the problem has to be a certian percent of the value. Like you cant get a new car or refund for leaking weatherstipping. Some States Motorcylces and other Hobby type veicles are not valid for the lemon law. Like Max said ask you lawyer.