Ah ok thanks,
Obviously I have been reading alot about this kind of thing lately lol...did see about running car with no cap on tbh about the airlock etc... would an airlock.make coolant leak tho?
But yeh the 2 coolant pipes front of engine font seem too much to replace if did that, like i say the guy said about the heater pipes but thats turbo side of the engine.
Will get it checked again I thjnk and even get them to do the dreaded head gasket test lol...as I say doesn't overheat etc,car runs fine just Obviously in my head I dont want to go on a longer journey for the coolant loss.
I know Obviously a chance of a water pump too which been told.around £600.
And I guess radweld is a nooooooo 😆 🤣
So, no, air locks 100% will not cause coolant leaks. its hard to tell from your pictures if the pipes are broken to be honest.
That black unit with coolant hoses is almost certainly the auxiliary coolant pump (often called the turbo after-run pump but also known as Auxiliary water pump, Turbo coolant pump, After-run pump).
It’s an electric water pump that circulates coolant after the engine is switched off its main job is to cool the turbocharger and cylinder head, preventing heat soak it can also run during certain driving conditions to help manage coolant flow.
They can go faulty but its not super common for them to break.
You tend to get coolant leaks from the pump body, Internal failure causing coolant circulation faults they are often replaced together with hoses because the plastic gets brittle.
Looking at your pictures, I am not convinced that pump is leaking.
- The top and side of the pump housing are dry
- The coolant staining looks baked-on and dusty, not wet or fresh
- The residue pattern looks like it’s been dripping down onto the pump, not originating from it
- If the pump housing seam or electrical body were leaking, you’d usually see, fresh pink/white crust right at the seam & dampness around the hose connections
Coolant leaks love to travel downward, and this pump sits low. Typical culprits are above it, very common leak sources above this pump on Mk6 GTIs can be, Water pump / thermostat housing (EXTREMELY common on EA888), Plastic housing warps or cracks coolant drips down the front of the block, Upper radiator hose connection, coolant flange on the cylinder head, expansion tank return hose & oil cooler seals (coolant + oil heat exchanger area rare).
Any of these will drip down and coat the aux pump, making it look guilty when it’s just the victim
My advice going forward before you spend any serious money would be, Clean the area with brake cleaner and get that pump super duper clean. Drive for a day or two, Recheck with a torch → the highest wet point is your leak.
Even better (But will cost money)
- Cooling system pressure test (cold engine)
- UV dye in coolant (shops do this quickly)
But, if I had to guess, I would agree, its likely the Water pump or Thermostat.
I agree with you, not worth replacing the Water pump unless your doing the timing belt as well, likely due anyway.
As for your Head gasket, these are not fords, you don't have to worry about that
