I have a 2005 3800 series 2 SC i am building for a sand rail. I had someone build me a stand alone harness and they tuned my ecm. Got it back and the motor will not fire. Put a scanner on it and was not getting signal to the injectors. They had me send the ecm back and then sent it back to me, told me the VATS was off. Put it back in and the same thing happens. Scan it and the injectors are not getting signal. Its like the vats are still on but they say they are off. Any help would be apprectiated.