why my iveco suddenly stall and when release acc pedal and press the problem solve

MAX, October 2015

Unfortunately you left us to guess which engine you have, so all we can do is provide general advice.

Start here: http://www.autotap.com/techlibrary/solving_intermittent_stalling_problems.asp

You may do better to find a dedicated Iveco forum (even better, one for the particular model you have)

XXXXX, October 2015