Okay, Well I just did that and my car jerked a bit when boosting but was able to get to full boost.
After plugging the hose and still keeping the wire unplugged, my car barley jerked but not getting full boost at WOT.
so im lead to belive that it could possibly be a bad blower.. because with normal driving things seem to work fine.
also after reading online, did wanna throw it out there but I have a 98 GTP TB on my 99 gtp..
not sure why, thats how I got the car baha not sure if that makes a difference.