I'm hopefully going to get an economical vehicle in the next year. I know that the Focus and some others are direct injection engines. But are the Prius / Corolla / Civic also direct injection? I am probably going to purchase a brand new vehicle, and was wondering if the direct injection vehicles have been having any issues. I saw that some of the Ford engines have been having build up on the intake valves causing a need for cleaning. Is this just going to be a problem with them? Or do some of them have all the issues worked out?