Opel Astra H has an electric driven throttle valve. As I know, coolant in throttle valve body would control bimetal plate responsible for warming up. Why can't it control warm up process based on thermo sensor? Why do they need to get the liquid to the throttle valve?
The throttle valve body inlet pipe (55354563) is really flimsy, besides it is designed for one installation only, it breaks if you try to remove it.
For me it looks like an intentional sabotage of z18xer engine.