As I help teach new users of TunerPro I will update this starter tutorial. I have forgotten what is was like at the begining. TunerPro RT does a lot! It's the only software you need to use for OBDI EFI tuning, but can be a little overwhelming at first because it does so much. So go to TunerPro and download and install the software. TunerPro just makes changes to chip/bin file. TunerPro RT does that and is also a scanner/data logger. Download and use for free, but please pay the $39. registration. http://tunerpro.net/downloadApp.htm For this start up guide we are going to use TunerPro RT and the 1227747 GM ECM which uses a $42 mask. this covers all the trucks in this forum. All ECM/PCM have a mask, they start with $ indicating it's a hex number (you'll learn what a mask is below) as you read this post, really read the whole post first then come back to do it again, then all files needed for this tutorial can be found attached to this post in a zip file. If you would rather use files for another vehicle but don't know which ones? There is a TunerPro Lookup Excel Spreadsheet to help find them here: http://www.gearhead-efi.com/Fuel-In...rPro-ADX-and-XDF-lookup!-Find-your-files-here! OK why do I need a mask to make changes in my chip? Well the file on the chip is called a BIN file, .bin is the extension on the end. It's written in computer languge called binary but usually worked on in hex and It looks like this. Ok where would you change the idle? Now there are guys here that know how to do this but still use TunerPro because it simplifies the changes because they are using software like TunerPro and a mask file so you can do the hex changes in english. Let's move on! You have downloaded TunerPro RT and installed it on your computer and opened it! Well there is a slight learning curve. May as well start by having a folder with originals from zip file attached and a set of duplicates to fall back on because you can change your bin, adx and xdf the way you want. You can also mess them up... Well with TunerPro RT you have to load a few things. It may take a few times reading this to sink in. First your bin/chip/ for this tutorial we will use ASDU.binwhich is for a 1990 5.7L Suburban. If you want a differant bin file that matches your truck it is probably here: http://www.gearhead-efi.com/Fuel-Injection/showthread.php?304-1227747-ECM-Information-42 Then you need the mask (xdf) to read the bin in English, not hex, $42-1227747-V5.xdf Then you need the file for data/scanner (adx) file for the bin/chip/ECM which is the $42-1227747-V5.adx The data logged is saved in a file with .xdl at end and can be named anything... you do not need this but it is in the zip folder so you can see what a data log looks like and play it back to see how your engine is doing and where changes need to be made. It is file named 11-27-11-3.xdl With TunerPro downloaded and installed open it. Then... 1. CHIP: .bin extension. TunerPro, File, Open Bin. Choose your bin you downloaded and saved. Now your bin is loaded in TunerPro. 2. MASK: .xdf file extension. TunerPro still open, XDF, select your xdf you downloaded and saved, now your mask is loaded in TunerPro. You can now make changes to your chip/bin file. 3. SCANNER/Data Logger: .adx file extension. TunerPro still open, Acquisition, Load Definition file you downloaded and saved . Now your acquisition file is loaded in TunerPro. You can now record data from car. Or play back a data log if you do next step. 4. DATA LOG: .xdl file extension. TunerPro still open, Acquisition, Load Log file. Here's some more so you don't have to do this each time you close and open TunerPro. Tools, Preferences, General, check the box to load your last xdf and bin at startup... I have everything on left side checked, right side your choice, I would leave default for now, then over to Data acquisition and Emulation and check load last adx at start up. Now you will have your files ready each time you open. Also if you make a change and forget to save it will remind you if you close it. Maybe you were playing and do not want to save? I also tell guys to right click on tool bar and check all tool bars! Get used to the buttons, they are the same as going through the menu items. There's a start! HTH! You should now be able to play with, change, improve or mess up anything!