what is this and why is it like this?

lifted up my hood to check out my temporary intake and i heard this buzzing noise...looked around the engine bay and spotted where it was coming from...looked like it was ready to pop
http://img112.imageshack.us/img112/6997/dsc01528uk4.jpg
http://img169.imageshack.us/img169/8821/dsc01529zl4.jpg
i tried looking it up in the shop manual, but since it's on my pda it's a lot to look through so i'm d/l it at the moment, but slow connection owns me...any help on the reason this happened? as far as i know this is the first occurance

Those are the ac lines noob :P Thats your evaporator poking through the firewall. There is not pump in there so it wont pop. Also for the buzzing, check your iacv..mine makes a buzz/tone when the power is on. It is a solenoid after all.

i thought it was the heater lines, but i never worried about a/c before, so this is something new to me, but this was the first time i heard the buzzing noise...probably by chance that i did hear it

The heater lines are more to the right..under the intake. And there is a cable operated valve on it.