BOV constantly open

[CvicKila02]

Okay here’s my dilemma. Recently my idle once my car warms up is 3,000rpms , now to add to this wonderful problem my BOV seems to be open just a little bit under idle . I have a 1G crushed BOV and its been working fine for 8 months now no problem holding boost. Now it sounds like a high pitched whistle when its at idle almost like what a semi sounds like under acceleration. Just wondering if anyone could help me out and figure out what my problems are.

Thanks,
Dave

 

[Dan7040]

It is normal for a BOV to be open during idle and part throttle situations. This is one of the many reasons that venting a BOV is bad. The reason there is a high pitched sound is probably because your car is idling at ~3000 RPMs. Fix your idle problem and Im sure your BOV is fine.

 

[CvicKila02]

I've had a the crushed BOV on my old 1G, and it did leak a little. This leak is like a high pitched wistle thats constantly sounding whenever i'm idling. I do think i have a Boost leak somwhere which i have to fix but i'm waiting for my boost gauge to come in so i can check that when i pressurize the system. Could vac leak cause my BOV to be open i guess is my question. Also i have a clear tube that conects my bov to the intake so i don't vent but i've noticed that is coated with a film of oil? could that affect the BOV if oil i gettin into it?

 

[CvicKila02]

Its not leaking in the form that you guys are thinkin, I know what leaking is. This is more a high pitched wistle when at idle, this BOV did leak a little a while ago cause for the hell of it tired venting it and put my hand over the bov end and it didn't allow it to leak but when i removed my hand it idled bad ie it leaked but there was no high pitched wistle. Now its making a high pitched wistle.

 

[WhiteTsiAwd]

Weird. I have the same problem. Well my bov "leaks" at idle aswell as doing the really high pitched whistle. I am venting right now b/c i made my own UICP and in doing so i messed up my bov return tube and so I am waiting to put my new intake on before I find something to use as my return tube.

But from what I know, the bov is supposed to leak a little at idle. Why? I have not a clue, sounds like a dumb idea to me but I guess that it is supposed to. So try and not vent and it should go away.

Sorry I am not of much help.

 

[bkblazen2003]

it leaks because vacuum is high at idle. bov is meant to open when vac is present. for example when you let off the gas you go from pressurizing the manifold to a vac situation. than it realeses

 

[steve]

A unmodified 1G BOV will be open anytime there is about 7-8 psi(I forget the actual number) difference in pressure between the reference port on the bottom flange and the nipple. Crushing it will raise that number since your increasing the spring pressure.

That doesn't count the leakage that seems to happen around the shaft to the lower reference chamber after they get old. If the BOV is vented that leakage path could easily be whistling as could a leak at the flange.

Steve

 

[GriffLaserRS]

My 92 LASERS BOV stayed open at any boost. The car wouldent boost for crap. I took off the recirc hose and could stick my pinkie in it at idle. If I pushed the valve down by hand it would start to stick half way and wouldnt spring back. Tossed it replaced it and boosted again.