Turbo question. Strange noise

[old_jameson]

Hi everyone!

I have an A3 1.8t 1997, oettinger chip.
And here's my question.
In the morning, while the engine is cool, there is no problem - everything works as it should - but after some time, when engine reaches it' s working temperature - strange noise is comin out from under the hood - it seems like some pipe is making that strange noise like the air is coming out - like a grasshopper.
Does anybody had something like this in experience?
Please feel free to share the experience.
Thank You in advance!

Regards,
Olafs

 

[Matt82]

the sound of a turbo compressing air into an engine maybe?

 

[old_jameson]

No - I doubt, because that noise is a little bit different - that what comes out of my engine is not regular frequency, also probably it could be the turbine wings? That sounds like metallic - but also can be heard like aero-mechanic.

 

[Matt82]

when does the sound occur and what does it vary with?

 

[old_jameson]

The sound occurs when I accelerate strongly. When I drive smooth - the sound won't come out such loud. When engine is cool - everything runs well. And just one more thing - when engine ir warm, it feels that the power of torque also goes down, it wont accelerate so strong.
Sorry for my english - I am trying to explain as much as I can.