I have a 2008 MY08 wrx hatch and there are bubbles appearing in the cooling system, the car is well looked after with 84k on the clock and the car is still standard with no mods done, the oil is not milky and it looks fine, there are no visible coolant leaks either, the temp is normal no overheating. I'm just wondering the possibility of the head gasket leaking slightly? is it common on my model? and what's the best way to get a good idea without taking the engine out? or can you remove the heads while the engine is still in the vehicle?
OR the bubble issue maybe something simple to fix, I don't know
Forgot to mention it drives like a dream no roughness or anything