Very odd engine noise - Video inside

[ethos]

Very odd noise started today, it's a highish pitch squeal that doesn't seem to be set off by anything (e.g. accelerating, braking or cornering). When you turn the engine off it sounds like it is releasing a lot of pressure (not so clear in the video) plus the audible squeal that occurs. I can hear it from the drivers wheel area fairly consistently when the engine is running, but it does get louder whilst driving. 

 

Any ideas?

 

Thanks

 

https://vid.me/BrcW

 

Edit: I should mention that the coolant level light has come on a few times recently- but the coolant level in the expansion tank hasn't moved and looks fine. The level sensor for the coolant is in the expansion tank itself- or is it somewhere else in the system?

Edited 23 January, 2015 by ethos

[ethos]

I've just started it again, noise was immediately present so doesn't seem temp related.

 

There is a lot of pressure being released and a noise of water 'moving around' when the engine is turned off. Sounds like it's from the front of the engine but it's really hard to suss out exactly where.

 

I'll get it booked into my garage tomorrow or Monday, but would be good to get an idea of what it could be- so I can either try and take a look or prepare my wallet. I'm not going to drive it until then... 

[ethos]

Started the car a minute ago, completely cold. No noise this time, but I didn't get the car fully up to temp. Any ideas on what the noise in the video could be?

 

I'm tempted to take it for a short drive to see if it reappears... 

[ethos]

Not that anyone cares (!) but this was down to the PCV valve. You can confirm by pulling the dipstick whilst you can hear the whistling- the noise will disappear. 

 

New PCV valved fitted for ~£50. 

 

https://www.youtube.com/watch?v=ReyIpPCnwJ4

[Phil-E]

Wonder why nobody replied?! lol

 

I was going to suggest the PCV as soon as I watched the video but looks like you're worked that out now.

 

Phil