[Ozzie55]

Sometimes when I go up a hill I can hear a slight blowing sound - the only way I can describe it is it sounds like when you blow down a beer bottle. for a second and then it goes. It's very inconsistent and doesn't happen all the time. The car drives perfectly well and gear changes are smooth etc.

Does anyone know what might be causing it - it sounds like it's coming from the exhaust - rear of car - but I'm not exactly sure.

I took my car into BMW last week and the technician drove the car with me sat in the passenger seat and he heard the noise once but said he would need to hear it more often than that so you might need to let the issue develop so the sound becomes more frequent and then we can diagnose and get more of an idea of where the sounds coming from!?!?

After they investigated they said the intake hose was slightly loose and that was the issue but the noise is still there.

Any one had any experience of this? It's driving me mad