Hi lads my 3dr is doing my head in at the mo it's running so well but every time I bring the car on boost it pops the stat and the motor goes cold and when I take it apart it's stuck open . But if I drive it and don't boost it it dose wot it should do . I'v got it in my head that there could be a crack in some thing but as the car works well when I drive it as it should be and it dose not use any water I'm puzzled any help would be grate