Zauvzi

Hey everyone,

first post here, just bought a 2004 Audi A4 Quattro 1.8t, bought with the intentions of fixing up.

Been having issues determining the cause of my system lean code. Checked the pcv for leaks, checked the vacuum hoses located at the back of the valve cover and the crankcase regulator valve, all seem to be working as intended.

Only thing out of place is I can hear a quiet whistle coming from below the regulator valve, but can't actually pin point the leak.

Spent hours upon hours trying to find the issue.

ANY advice or information from people who have had a similar issue is greatly appreciated, I just want the poor thing to idle right.