GFB Hybrid BOV only works 50% of the time? (Pics)

[Silver Surfer]

Hey guys, I purchased a GFB Hybrid BOV for one of my old 2000 GTB wagons around 2 years ago. My sister has the car now, so I removed and swapped the OEM on mine and got my GFB off hers (same year vehicle/model). Everything went in sweet, simply switch. However, the BOV only works around 50-60% of the time. Not sure if it was doing it while on her GTB as she wasn't sure how it worked or "not sure how to make it sneeze" lol I didn't think of trying it as I figured it'd be a hassle free install.

It usually always works when cold for that drive, turbo pressure build up then PSSSSSH. I'll then park it up for a few hours, say, to clean the car, take it for the "dry down run" and it'll be quiet. You can still hear it....JUST. It's only making, I'd say, 10-20% of the full noise (100% being the PSSSSSH!). I've checked all the lines and everything is in check, no leaks, return hose is bunged and clamped, hoses are tight.

The only thing I can think of is perhaps the spring adjuster screw. I searched but nothing useful. Could the screw be too far out? Having said that, I just put the screw pretty much flush with the actual exterior of the BOV surface and it still did nothing. I thought, maybe adjusted all the way out (very loose) would mean the valve and spring would open a lot easier resulting in the PSSSSH? Any ideas, help or input is much appreciated. Always the way, little things annoying yah grrrrr!! lol

Cheers,

Carl

[Kiwi_Fozze]

seat pressure too high?

if it is, you'll have some compresser stall too. mine does.... makes me cringe.

[Silver Surfer]

Sorry to be a dumb ass but what do you mean exactly? Doesn't sound good, me and turbos are not the biggest of intellectual partners.

[Kiwi_Fozze]

lol, i know its an issue with mine, as the bov is actually a touch small for my car. its the spring pressure that holds the valve closed at idle. loosen it off, it stalls at the lights but vents lots of pressure, too tight it won't vent any pressure, creating the surge. erm....

i dont quite know how to explain how to set it

[Guest]

silly question but are you making sure your coming on boost then taking your foot off to change gears? becus on my old twin turbo i had 1 bov for the 1st turbo but none for the 2nd. and of course none for the " valley of death " i think they call it.. in other words are you getting enough boost to open the bov, or any boost at all

[Silver Surfer]

 kwi_fozze said:

lol, i know its an issue with mine, as the bov is actually a touch small for my car. its the spring pressure that holds the valve closed at idle. loosen it off, it stalls at the lights but vents lots of pressure, too tight it won't vent any pressure, creating the surge. erm....

i dont quite know how to explain how to set it

Aha, thanks I get yah mate, I've had it loose and had it tight, now, on to the cars hahahaha, lol, nah but yeah, I've had it set both ways and still quiet. With the spring and screw loose, it definitely made more noise more often though. It's back to tight so I'll loosen it tomorrow. No effect at either end on idle though.

[Silver Surfer]

 CIutch Nade said:

silly question but are you making sure your coming on boost then taking your foot off to change gears? becus on my old twin turbo i had 1 bov for the 1st turbo but none for the 2nd. and of course none for the " valley of death " i think they call it.. in other words are you getting enough boost to open the bov, or any boost at all

No silly questions mate, it all helps. But yes, I know how to get them to work and build up plenty of psi, that's why it sucks. It's like, build up.....rpms up, you can feel the car on boost and under pressure per se, easily, then......*duck fart* lol. Nothing. Just a little psh which you can JUST hear, passengers or people not actually listening for it would miss it, it's that bad. So it's not driver error, put it that way. Thanks all the same!

[Silver Surfer]

Should I open up the BOV and just give it a bloody good clean? Maybe the actual valve is a little sticky??? I doubt it but yeah, that's all I can come to at this stage. Hence me asking you guys, the pros. Do BOVs go faulty often, like, is it common??

[Kiwi_Fozze]

i soaked mine in crc and kero then oiled it up a bit when i installed, but it was an OLD second hand unit.

*shrugs* its a gfb unit.... i've not heard of one crapping out

[Silver Surfer]

Hmmmmm, might have to give that a go, nothing to lose at this stage. Thanks!

[neodowd]

Have you got somebody to rev car while you look at b.o.v to see if valve is opening and closing as it should ? I sprayed crc on my b.o.v made it work better.

[Silver Surfer]

Nope but just as good, throttled it under the hood and watched it at the same time, it's just not opening. sometimes it will, like first run or so of the day and it MAY work again later just depends, very variable when it works, annoying as haha.