Yes the noise occurs at idle and even if I slip it into N
Yes and it is so loud that pedestrians can hear it.
OK. Thanks for that. I will have to wait until the weekend to have a look.
Saturday Midday and have just taken the car for a test drive after fitting a new fuel pump and inline filter. Unfortunately the whistling noise is still there and just the same.
Yes it was the whole unit compete with white housing and fuel level float. The old one was quite orange and brittle so it needed replacing anyway. I also replaced the metal inline fuel filter as the old one looked as though it had been on for some time.
I think I have found what the noise is. There are a couple of vacuum lines at the left hand rear of the engine and it would appear that this is where the noise is coming from. Anyway I will have to remove the air intake and have a closer look at it all.