Citigo 1.0mpi strange noise

[Fabiasi]

My wife's citigo has developed a rather strange noise from the engine.

It is a continuous woooooooo noise and if you place your hand over the air intake of the airbox it stops.

Again if the little pipe from the airbox is removed and covered with your finger it stops.

 

My thoughts were that it was the PCV valve in the rocker cover but I have replaced this and the noise is still there ?

 

It definitely seems worse when the engine temperature is cold.

 

Has anyone else had this or is it possible it's something that we just haven't heard before ?

 

Thanks Simon

[Fabiasi]

Anyone ??

[mac11irl]

Does it sound like its maybe a vibration resonating in a pipe that has been slightly loosened/tightened kinda like how sometimes if the water pressure drops a smidge in your house the flow starts vibrations the pipes and they hum?

 

 

[Fabiasi]

Sorry for the delay in responding,

It's possible but why would it disappear when the intake is blocked off 😕

[freemansteve]

A pressure change in a hose can change it's stiffness, hence the way it resonates. Anything can change if you put your hand on it.

 

Is the noise more like a pure-ish tone (low pitched whistle) or buzzy (a mechanical resonance)?

 

Can you post a sound file or video - someone here may recognize it if they hear it!

[Fabiasi]

The noise is more of a pure-ish sound .

I will try and upload a video later 

 

Thanks

Simon

[Fabiasi]

Righty then,

Hopefully you can hear the constant whistle noise in the attached video clip