I have a 2016 1 litre ecoboost 123bhp fiesta. When driving I found hot air coming through the vents. ( the heat was not on) I pulled over to find the coolant boiling. I have brought it to a mechanic who changed the water pump and a thermostat and told me the issue was resolved. I drove the car to work the next day approximately a 45 minute commute. I opened the hood to find the coolant bubbling again. The temperature gauge in the car shows the car isn’t overheating. Any advice on this

Getting air in somewhere

Get the head gasket checked

My mechanic says it’s not the head Apparently there is another  water pump that circulates water from the turbo and that bubbling may be normal but I’ve never heard of that before 

Yes on the 1.0 EcoBoost there's an electric pump that keeps the coolant circulating after switch off.

Initially only fitted to Focus's with a towbar, but then fitted to more, possibly all, later on.

So it should be safe to drive or should I try get rid of it

13 hours ago, Adrianlynch said:

So it should be safe to drive or should I try get rid of it

As long as it's just bubbling from water movement, not boiling from excess heat or building up pressure in the pipes, then it's doing what it was designed to do and is safe to drive.