Coolant loss from top of expansion bottle/ cap.

[Luckylucas]

Hi to all
I've got a problem with coolant loss from expansion bottle top cap.
Every now & then low coolant light will come on & bottle needs topping up, usually after a good run out!
Clear signs of coolant being blown out top of bottle & around o/s inner wing.
I've replaced expansion bottle & cap but still I have a leak ?
My car is a 2014 A3 2.0 tdi quattro 184hp auto.
Any help much appreciated

 

[JohnM100]

As you have changed expansion tank and expansion cap/o-ring suggest looking at thermostat, air-lock, or water pump. Diesels tend to be more thermodynamically efficient than petrols so some of the petrol reasons wouldn’t apply.

 

[Luckylucas]

As you have changed expansion tank and expansion cap/o-ring suggest looking at thermostat, air-lock, or water pump. Diesels tend to be more thermodynamically efficient than petrols so some of the petrol reasons wouldn’t apply.

Thanks for the reply, a few things to look into then & hopefully it will sort itself out.