Anybody know what this part is?

I can't for the life of me figure out what this hose is, can someone help me? I just replaced the water pump and am now throwing an egr code and found this broken. (Second pic, first is for reference where I'm looking)

It’s for the pcv system I believe. You should be able to replace it with hose from auto parts store


Can you post the actual code you’re getting

It's p0401

Did you mess with any hoses near the firewall

I just replaced the water pump, timing belt and tensioner. Besides that I've only checked filters and such.

So no lol

The symptom I'm facing is an odd idle. Sometimes it's sitting around 1100 and sometimes it wants to drop into the 300-400 range which occasionally causes a stall but most times it recovers on its own