I bought a 2006 Etec from a dealer. After I got the title I talked to the original owner. He said that the motor was on it's 3rd power head and on the 3rd power head he had to put a fuel injector in #3 cylinder. Lost #2 cylinder on both power heads. He said he ran synthetic oil on the first 2 power heads and went to 50/50 on the 3rd. Is this a common problem that I have not heard about or did I just buy a lemon?