I recall there was a tread on here recently about air/vacuum leaks on the BMW V8. I'm pretty sure I have one on my Jag-engined Vogue.

Have noticed a quiet whistling sound for a while but thought nothing of it. Also, the car changes down much more frequently going up long motorway hills at motorway speeds, and feels a bit down on power.

Yesterday I did 550 miles (!! Yes, my ageing parents had a car crash near Bradford, we all live in Kent and guess who had to collect them!) and had plenty of opportunity to work out what was going on. The whistle is only there when the throttle is open, it get slightly louder if you give it more gas, and disappears when you lift off. So all in all I'm sure I'm looking at an inlet leak.

Any clues for obvious/common points to check on this engine? Otherwise I'll have to try and work my way through the system as far as I can.

Thanks in advance.

Quick bump for the weekday crowd!

I had a look last night, I *think* there's a slight whistle coming from the area of the back of the engine, where the vacuum pipes run around to the servo. Tried to "stethoscope" it with a piece of tubing but it wasn't long enough, so I'll have to get a new bit.

But all other suggestions welcome! Could it, for example, be the round, flat breather on top of the RHS of the engine?