hi guys, just recently my focus st2 has start making a howling whistling noise (when foot is takin off throttle). It does not start untill about 5-10 mins after i start to drive. its like a very loud whistling noise whilst stationary in neutral or wenever i take my foot off acceleration when driving.. ive took it too 2 garages and neither of them have a clue.. ulness they start takin the car to pieces, but i wanna know what it is first. The car is running ok but i dont want to drive it incase i cause anymore damage.. any help or opions wud be appreciated.. thanks