Can anyone identify this?

[immac]

Can anyone identify this box on my Audi A3 1.8T 8L 1999. It is on the back wall of engine bay to the right. The cap is missing and there seems to be a diaphragm. What does it do, what is it called?
I´ve borrowed this picture off Internet (not my car) and circled item in question.


Thanks

Ian

 

[Lavis89]

isn't there usually a relay in there? i might be shooting in the dark a bit here but people usually remove this box and put the relay in the trunking next to it when mounting a oil catch can

 

[BENJAMIN]

Barometric pressure sensor. Measures atmospheric pressure to compensate your cars fuelling/timing.

 

[Lavis89]

Barometric pressure sensor. Measures atmospheric pressure to compensate your cars fuelling/timing.

yup i was definitely shooting in the dark. hahahahaha

 

[immac]

Thanks guys! One of the problems working on this project in Turkey is the language confusion. This answer addresses another problem we were having on the diagnostics which were showing a "height" (in translation) problem, which we were trying to deal with. Because we could see a small diaphragm on this fitting we guessed it might be something to do with it, but were not sure.

Ian