There is a pipe that goes from the intake mani to the top of the black box (PCV?) on the rear of the engine.
When i had the engine apart that pipe was brittle and hard and broke, what will happen if i run the car without this pipe?

 

you'll have blow by gases exiting to atmosphere instead of being reburned, and it could result in a vacuum leak due to intake manifold vacuum acting on the pcv valve.