If the person who sold me my car new it had a bad engine are they responsible. I know theres a lemon law but what if you find out after the 30 days.

You would have to prove they knew the engine was bad when they sold it to you which is very difficult to prove.

Define "Bad engine" How many miles did you drive the car? How many miles was on the car when you got it ? ~~~30 days is a fair amount of time for a 10 year old car to be evaluated. Don't automatically assume the dealer knew that it had a bad engine because they probably got the car on a trade in and may not have known the cars true condition

wellI just found out today its the pistons and it has just over 100 thousand and 30 days it is a fair amount of time for someone thats not a first time buyer. and just now learning that some will F*** you over becuase the odds are they did know. But theres not a thing I can do about it. But live and learn.