Boiling coolant after stopping....pours out of overflow
Firstly, an apology. I'm sure that this is answered somewhere, but I can't find it through the search engine.
I have a 2009, 9-3, 2.8 V6 convertible. Have had it for all of 2 months (first Saab) and I am consistently getting coolant low message. Top it up, don't lose any coolant while driving, fan coming on and off fine, water temperature stable and in middle of range etc. etc. But then I found that having stopped the coolant in the reservoir is bubbling away and coolant pouring out of the overflow.
Not 100% confident in cap, goes on OK but not as nice as I'd like. Before I take it to local garage and get told to have a new pump, reservoir, hoses etc. etc. I wanted to ask for input from the wisdom of the forum.
Appreciate your help.....could it just be the cap (clutching at straws), is it worth swapping out the reservoir myself, is engine actually overheating?