I just bought a 06 mustang gt it already had a 62mm twin bbk throttle body on it. When I test drove it it was fine but a day later I got stuck at a light because the throttle was not responding at all and a red wrench light came on. I looked in to it and everything was pointing to the tb. I looked up what the voltage should be set at and ended up setting it at 1.26 (it was at 1.38). Now if I start the car it has the light on and throttle won't respond and its idling really rough. I'm not sure what to do next?? Please help me out.