As to the OP ... if it blew the valve out of the grommet, you have a blow by problem... have you put a gauge on the dip stick tube yet
didn't blow it out of the grommet, this was a breather stuck down over the filler pipe coming up out of the valve cover. the other breather is tighter, and has never been an issue. this one was looser, and i wondered about it when i put it on, but figured it would be ok. apparently not.
as far as the gauge, i have a pressure/vacuum gauge, but i'll have to rig it up with the right fittings to go over the dipstick, i haven't done that yet. will see if i can get to that this weekend.
Get the fitting that will fit the gauge to hose, then clamp the hose onto the dip stick, run enough hose so you can tape the gauge to your windshield so you can watch it during driving