If you horn down the horn button and turn on the truck it will go into a service mode. Use the thumb control until is shows pn, then hit the horn button. I think it is number 2 for acceleration adjustment. hit the horn button when you get to 2 that will access the adjustment. Use the thumb control to move the number up and down. You have re-enter that setting every time you test drive and want tot readjust.

Hopefully this helps.