[fraktal]

your recirc valve is a bov. it's just the air that is purged is recirculated back into the system.

the reason you are having stumbling issues is because you are losing air that has already been metered and calculated for by the mafs. the ecu determines the amount of fuel based on that metered air. by venting to atmosphere after the mafs you are losing some of that metered air causing a rich situation which you see with your stumbling issues.

venting to atmosphere is just a sound...is it really that important vs. having the car run properly like it's supposed to?

 

[fraktal]

yea iv been doin alot of readin on this subject, but should it run so bad at idle, could this be a sign that the dump valve is leakin?

yes. either that or whatever you used to plug the hole on the turbo inlet is also leaking.

honestly do yourself a favor and put the recirc hose back on

edit: if it's not even idling correctly then you have a leak somewhere.