My 2004 plane goes out frequently

Hello friends, I have a Nissan Platina 2004, the matter is when the car is cold, but after half an hour when the revolutions come down they go down and turn off, sometimes it sometimes turns on quick The same if I get to another traffic light I don't know what is help me please! Thank you, since it has been reviewed by several mechanics and they have made tuning, injector washing and do not know why the failure,

Check the ground cables and clean up the acceleration body, they can be damaged cables or spark plugs