if that's what "nissan" meant. You can "search" here to see all the horror stories about dealers. (You now have your own example: "tampered with the ecu to where it doesnt show an bad codes" .... really? He said that?) Find a Z32 specialist near you. You can ask on this site. You can also search here and learn how to read codes yourself. Be patient. Search and read this site daily. You can get great help here, but search first. You just bought the car, it will take some time for you to know what to do to maintain it. To own a Z32 you either have to be rich or willing to learn.