MK 7.5 fiesta turbo not cooling down

[Tonyhamblin]

Hello I’ve got a 2015 Ford Fiesta zetec s 1.0l Eco-boost and recently it’s been feeling abit gutless like if I’m doing 40 in fifth gear I’d feel like I’d need to drop a gear to gain any speed, I’ve had a look at everything and I’ve made sure all the pipes are connected and no split and stuff, all of that is okay but what I have noticed is that after a long journey my fan use to turn on after turning off my car which it rarely does anymore I’m not sure if that’s due to it being cold outside of is it’s just faulty and also my coolant use to bubble up which it doesn’t anymore and someone told me it does that when it’s cooling down the turbo after a long drive but I’m not sure if this is true. 

If anyone has any ideas please let me know  thanks