building physic problem

i’ve a little trouble in my project.
i’ve made a little scene with my drivable car.
on unity i play correctly and have no problem and 0 log errors.
when i build and run my scene,the car is proiected on the sky!I think is a physic problem,but try understanding builded problem make me crazy.
Any suggestion?

Check inside Edit > Project Settings > Physics. There could be something wrong with your physics there. Might also be the objects are penetrating so they are pushed out of each other which results in some objects being thrown into space.