A little over one week ago, I bought a 2000 Camry Solara SLE convertible from a local dealership. The "check engine" warning lamp has come on two times in one week. The first time, a valve (not specified by the dealership) failed. It's at the shop now for the second time. Aside from being a PITA, is this something to worry over? Specifically, (i) is the six cylinder for that year high maintenance, (ii) is this evidence that the former owner subjected the car to heavy foot type abuse, (iii) is this car a lemon? It's a nice car and a lot of fun to drive. But, if it's a maintenance nightmare, I would just as soon be rid of it sooner rather than later.