It's the kind that has polished housing, with selectable 50/50 vent recirculation.
Installed about 4 months ago, customer came back yesterday said the car sounded like leaking if he's boosting...
Problem : the piston was stucked OPEN and leaked like hell.
Solution : Spray some WD-40 and push/move the piston and it finally popped back up.
We have never seen cases like this before on Japanese brand BOVs. It's not a big deal, but it can be harmful if those do not know what's wrong and keep their foot on the throttle, the turbo will be gone soon.

Installed about 4 months ago, customer came back yesterday said the car sounded like leaking if he's boosting...
Problem : the piston was stucked OPEN and leaked like hell.
Solution : Spray some WD-40 and push/move the piston and it finally popped back up.
We have never seen cases like this before on Japanese brand BOVs. It's not a big deal, but it can be harmful if those do not know what's wrong and keep their foot on the throttle, the turbo will be gone soon.

Registered User
If you someone can't open the hood and figure out that the really loud hissing is your bright shiney BOV stuck wide open, then they shouldn't be modding and driving a WRX.
On a related note, you probably haven't seen cases of this with other BOV's because those people were smart enough to periodically wipe it or spray it to keep it clean and functioning smoothly. It's a part exposed to combustion gasses...of course it's going to eventually get some carbon buildup.... same reason it's intelligent to clean out the throttle body once in a while to keep the butterfly working as it should.
On a related note, you probably haven't seen cases of this with other BOV's because those people were smart enough to periodically wipe it or spray it to keep it clean and functioning smoothly. It's a part exposed to combustion gasses...of course it's going to eventually get some carbon buildup.... same reason it's intelligent to clean out the throttle body once in a while to keep the butterfly working as it should.
That's one of the problems with piston-drive blow-off valves, the metal to metal contact causes a lot of friction and occasional sticking. I had the same problem with my TurboXS H-RFL. The diaphragm valves (SSQV, GReddy-S) nullify that issue but sometimes the rubber tears so pick your poison.