My car already had a jrsc when I got it. it has 440 injectors a cold air kit ,2in headers and 3in exhaust with no cat. It seems to run grate but the check engine light wont stop. I got the code checked was told it was the rear 02 senser so I re placed both of them and no change. Then I was told that sence there no cat I need spacer for the rear 02 bung. Did that, no change. SO I don,t know what has ben done to the ecu but I assume something was because there is a usb cabel comeing out of it. So my question is duse that mean I have kpro and if so can use it with any lap top or do I need a program to make changes to the ecu. And is there a way to program it to run with out a cat and not set off the check engine light. Or do I just need to put in a cat?