Long story short: found a loose hose hanging around in engine bay. Discovered its flexible and comes from the front (near bttm of radiator but not rad itself) comes up and around engine block to the air filter box housing. Approx 11/4" wide. Any idea what's this used for as no lights have came on and it's running and idling fine??!! 2001 octavia vrs standard btw. And sorry for the quick and illiterate wording as in a rush. Any help much appreciated. Thanks

probably just a run off pipe mate

It sounds like the pipe from SAI pump.

does it sort of click lock into the airbox and is hard but flexible corrugated like a hoover hose?

Sounds like somebody may have removed the SAI but left the pipe for some reason??

Not my photo.

I'm talking about the pipe with the blue filter on the end of it here towards the right of the photo. ( nothing to do with the red ring)

Edited 4 December, 201213 yr by michael1

That's the SAI hose which normally terminates to the air box.

Hey thanks for the replies. Yes Michael1 that's it exactly! I'm not that technically clued up - is this something I should worry about because at the min it's tucked behind the battery housing? If this does need sorting is it just a case of a new hose back into the box or can you easily use a filter like in the photo posted?? Thanks again in advance

underneath the alternator there should be, or will have been an air pump. yours may be removed as they become very noisy with age on cold starts. They are there to get the catalytic converter up to working temperature quickly. If yours is removed properly there's nothing to worry about! If the car is running fine, you're good to go!

Excellent help. Will have a look to make sure in the morning