I've had my car for 3 years skoda octavia 1.8t 4x4 from 2004 and I've just had to fill the coolant up a bit. However, when I went to fill it up I found this plastic part disintegrated. Pulled it out with scissors but have no idea what it's purpose is or whether I need to replace it or the expansion tank? Any help would be great!

Edited 18 October, 20187 yr by Woodsypaul

Part of the reservoir internals.

 

I've seen a few posts and YouTube videos on this.

 

Seems to be a VAG thing where the plastic used discolours and disintegrates.

 

I'd check the reservoir thoroughly and expect to replace it in case of failure at some inopportune moment.