This is a trimmed-down version of our MEFI 5 Scan & Tune^TM system for the user that just wants to do scanning / monitoring, data logging, and malfunction trouble code viewing. If you decide later that you want the ability to do tuning as well, you can upgrade to our MEFI 5 Scan and Tune^TM packages for just the difference in price between the MEFI Scan and the other package. You have nothing to lose by trying MEFI Scan first.