Bought a Lemon from used car dealership

Took a chance on buying an used Lexus Hybrid from an used car dealership lot. Bought "As Is". 2 days later I get a check engine light code for Cycling 1 & 2 misfire. Contacted them and they had me take it to their mechanic who switch engine coils to make sure it wasn't just the coils that were bad. Later that night same code goes on so I know its something major. I know this has to be a preexisting problem that they didn't disclose. I know I made the mistake of buying as is from an used lot but am I protected under any kind of law in California?