Volvo 480 Club Europe

Could someone explain to me what the 3 pipes emanating from the top left of the B20F engine are for?
Also what should they be connected to. The one nearest the front of the car always had just a piece of plastic piping over it but was essentially
open. My local garage said it should blocked of (the idle did improve when it was to be fair) bur after a week stood it refused to start until I removed it so
now I'm not sure.

Mine is a non AC 94 2 litre.

Cheers 480 people!

I assume when you say 'left' this is viewed from the front of car looking AFT?

FRONT pipe is blocked, i think it is blanked so that the garage can use it as a test point.
if the blank is removed idling is rubbish and it will stall on you at roundabouts when not fully hot , guess how i know?

MIDDLE vent/emissions from fuel system (although never have investigated)

the REAR goes to the vacuum sensor tucked in behind the bulkhead near windscreen wiper motor.