Hi, I currently have a IS250 that I like a lot but they seem to suffer from carbon problems. I walnut blast my valves and run premium fuel. Anyways I was in the dealer the other day for a coolant flush and really liked the IS300 but I want to make sure it doesn't also suffer from this annoying carbon deposit problem. Is the 300 a direct injection motor also? Does it have carbon issues?

 

No it does not. The Is300 and 350 has both port and direct injection so carbon buildup is not an issue.