Identity of component on engine.

[Lex Loofa]

Hi folks, 

I recently changed a pipe manifold for the auto box oil cooling and unwittingly had accidentally disconnected a small rubber pipe on a solenoid valve attached to a cylindrical component on the bottom of the engine at the front on the nearside ( as per the pics ). This LED to a ticking noise when the engine was running. I have now put the pipe back on and all is ok but I am curious as to what the component is. Any ideas please?

[ColinBarber]

I'm struggling to orientate myself with that picture but it's possibly the air suspension compressor given that you have an SE-L.

[steve2006]

Appears to be part of the vacuum switching system, the ticking noise was probably the valve operating but not finding a vacuum when it should have been present.

[Lex Loofa]

Yes thanks Steve, that looks like the offending article with the little solenoid valve beside it. That identifies it but the question now is what exactly does the vacuum switching system do?

[steve2006]

This particular one appears to be part of the evap system, other vacuum lines control the EGR system and provide brake servo vacuum on older cars.