I have just used a vacuum coolant filler today , the top hose and bottom hoses where the only ones to collapse under vacuum, not sure if it should be more.
The vacuum held at the recommended pressure so in theory shows there isnt an air leak.
I am still desperately clinging on to the last hope of fixing my car.
Just been reading up on Heater core problems and am wondering if this could also be a possible cause of my problem, maybe its clogged or something.
Whats the best method to bypass the heater core on a Bosch?