I have read the last couple of threads on problems with OBDII tunercat, but I have a different problem. I read the instructions and followed them very carefully, I started off by scanning it and saving my current settings. Well that worked fine scan said it was complete. I then made one EGR change and it would not dectect the PCM when uploading the new file. Then the car would only start by leaving the battery disconnected for a couple of hours. So tonight I tried starting the car after I just scaned the car and it will not start. Does anyone know why this is happening? Could this have somthing to do with the factory security system? Also do you think it would be ok to try uploading the new file after the car has sat for a couple hours? Sorry for all the questions I just do not want to mess anything up.