We just bought a car for cheap as ours was in an accident and the guy seemed so normal but lied and the engine has a ton of issues. 
so you got a lemon ? check your state laws
There is no warranty with private used cars. My hubby is a mechanic and saw no issues and drove it..However he then saw oil leaking when we got home and they had used the neon stuff all over the engine previously he saw under the black light..So they KNEW the engine was bad. So awful! We don't have a car now
Things like this happen all the time
Isn't it awful? People are horrible. We might just deal with a car payment every month now. As it's hard to buy from private sellers! So many are lying.