Chevy Monza desliga

I am new to this and I am looking for help, my chevy goes out, lights well and after a few seconds it empies to be slap and then turns off but I accelerate two or three times yy accelerates well and I release the accelerator and return to the same thing already on the way is the same is the first, second and third car all well under the speed or loose the accelerator and it goes out or it goes out and then it goes out and then it is of the head embalagem
se alguém puder me ajudar com isso, eu apreciaria muito