Yep thats it. The black thing with the 2 vacuum fittings. Its a check valve and is most likely the reason its not opening. A check valve only allows air to flow one way.

Don't know where you can get a new one, maybe call the company you ordered the bov from.

haha ok so funny story, driving to goto school started driving and then the car was just fine but after taking it out of every gear it would keep dieing. so i pulled it off to the side and looked and the BOV was wide open, pushed on it and it was completly open, so i took off the vacume line and it shut, i was like really suprised at first and also very confused. so i just put the adjustment screw in all the way, wasnt long enough to tighten the spring so i took the little nut off, and it then was long enough i have it in there as far as it will go put the houseing back on and started driving and WWWAAA BBBBBBBEEEEEESSSHHHHH. freaking loud. i love it. scared some kids getting off the bus. she was drinking something in a huge cup and she got scared enough where she spilt it all over herself. i love this thing already, oh none the less she was wearing a white shirt :). so i tweaked it up a little its opening at perfect time. before compression surge "so right when the throttle is let off" and stays open a little at idle. no fluttering nothing. that screw is just perfect lenght. is there a place i can get a replacement spring inside of it. all the parts that work on the REAL HKS BOV will work on the Knock off model.

oh and also i noticed that it will blow off when im not moving and i just rev the motor. i have been told that the BOV on the supras arnt supose to do it, it will only blow off when in motion. im not complaining though :)

nice. hey where did u get the knock of BOV from

just look here
its all BS Ebay shit. enjoy :)

Glad you fixed it. It's probably opening when you rev it in neutral because you cut the spring, not a good idea. Mine doesn't blow off when revving in neutral.

See I told you its loud :bouncy: