^^ it has fixed my problem so i think that was it.. Other than that, i havnt changed anything to the car at all!!
Got told by my mechanic that it will improve it, which it has.. Might not help on all cars, but im happy..
Im not to sure if you can just empty it.. Shouldnt cost you that much.. If you really keen let me know and i will go talk to my mechanic again and ask him exactly what it will do..
he just suggested me to change it, seemed fine ever since..