Wheel pedal settings! (Bug? Not sure)

Hey guys
So i have a thrustmaster 458 spider racing wheel and love using it but on forza 6 i am having a problem which I can’t understand. I have looked around all over the internet and every one is saying to have your acceleration deadzone outside set at 100 but everytime i do that the car won’t go when i am in a race, so i set it to 20 (the lowest) and then it goes fine but after every race the settings reset and the car doesn’t go again i am really confused and i need help please!