power loss and pink smelly gunk in the coolant?

[chocosweet]

I have just purchased a ford focus zetec 1.8 on a y plate.but have noticed that when i slow up at a junction or roundabout i lose power briefly.not all the time.but its scary.also in the coolant it is pink and smelly with squirts of powdery stuff over other parts and over coolant.would really appreciate any help please.thanks x