NEED HELP: BOV stopped "working"

blcknspo0ln · Jul 3, 2005

hey guys,
I'm pulling my hair out trying to find out why my BOV won't open anymore. when I had my 16G it opened up fine, then right after the 50 trim install, the damn thing won't open anymore.

Only mods done were a 50 trim setup and 1G TB. I'm going to try and source out the vacuum lines on my car [got a diagram], but what else could cause the BOV not to open.

Juts FYI, I opened up the BOV, cleaned it with MCCC and relubed the piston with lithium grease. I also did the SSM and the valve opens and closes just fine. It HAS to be a vacuum leak, but does anyone know any other reasons? broken BOV possibly?

*edit* just to ellaborate, I can hit 15 psi on the 50 trim and you can hear a faint comp. surge.

anybody have a good description of how BOV's work? Maybe if I can understand the theory, I can figure out whats wrong

92awddsm · Jul 3, 2005

blcknspo0ln said:
hey guys,
I'm pulling my hair out trying to find out why my BOV won't open anymore. when I had my 16G it opened up fine, then right after the 50 trim install, the damn thing won't open anymore.

Only mods done were a 50 trim setup and 1G TB. I'm going to try and source out the vacuum lines on my car [got a diagram], but what else could cause the BOV not to open.

Juts FYI, I opened up the BOV, cleaned it with MCCC and relubed the piston with lithium grease. I also did the SSM and the valve opens and closes just fine. It HAS to be a vacuum leak, but does anyone know any other reasons? broken BOV possibly?

*edit* just to ellaborate, I can hit 15 psi on the 50 trim and you can hear a faint comp. surge.

anybody have a good description of how BOV's work? Maybe if I can understand the theory, I can figure out whats wrong

Did you hook the bov hose to the top nipple or the bottom nipple? Try the hose needs to be hooked to the top nipple and leave the bottom open to atmosphere. If it is hooked up like that, you might want to loosen the adjustment some(softer) and see if that helps. Also check the hose for cracks or tears. I cant really think of anything else at the moment.

dremersvision · Jul 3, 2005

i would mess with the tension on the bov because it might be to tight but you would think that with a 50 trim it should be opening up just fine.

marcmsj · Jul 3, 2005

be sure you hooked the vaccuum line back up to the bov...

if it's hooked up, try a softer setting on the adjustment screw.

blcknspo0ln · Jul 3, 2005

I've tried it all, NEW vacuum lines from IM to MBC, new brass Tee fitting... the vac. line is hooked up correctly to the TOP nipple, and the bottom one is vented..

i'm getting sad

Going to swap out my type S with a friends to see if the BOV itself failed..

I also tried backing the screw out.. i'm talking about there's about 10-12 threads sticking out now.. the BOV is at 90% of how soft it actually can be. At this point I was sure to hear flutter, but nothing.

any other input? thanks again..

marcmsj · Jul 3, 2005

can you open up the bov by hand? maybe it's stuck...

blcknspo0ln · Jul 3, 2005

I did the single spring mod to the type S so it actually opens up EASIER than a normal one. but yes, I can push the valve in with my hand with a little effort.

marcmsj · Jul 3, 2005

i'm not familiar with the single spring mod... got a link to it?

i'm running out of ideas here. is your bov recirculating?

blcknspo0ln · Jul 3, 2005

just search for SSM... you basically remove the smaller spring inside the BOV to help with flutter..

PieEyedPiper · Jul 3, 2005

maybe try putting the spring back?

washed_up_talon · Jul 3, 2005

PieEyedPiper said:
maybe try putting the spring back?

yeah maybe you should try that

fostytou · Jul 3, 2005

check the vaccuum line running to it... my lines were getting sliced by my cruise control after I got my FMIC and short route piping

blcknspo0ln · Jul 3, 2005

checked all vac lines and replaced them [even though i probably didn't need to] ...

I also DID put the other spring in, no difference.

Now i've also swapped another BOV [a different type S] and sitll no improvement.. i'm getting pretty desperate here.. I have a 50 trim turbo and I'm too scared to drive it

Shadowofoblivio · Jul 3, 2005

have you tried hooking the line from the BOV to a different spot on the manifold?

blcknspo0ln · Jul 4, 2005

it's too late to try now, but I think i'll do that tomorrow

Patterson · Jul 12, 2005

well i don't think it's your bov, otherwise your buddies would have worked. perhaps the pressure source from the manifold??? :confused:

Zexell · Jul 17, 2005

Im stuck on the same boat. Any blow off valve that I put on, they all sound the same. My 1g bov, 1g crushed, and my type S, all sound WEAK. I spent all day on it yesterday but got nowhere.

droptopgst · Jul 19, 2005

I had the same problem with mine when I put my 50 on. No clue what the problem is I got sick of trying to find it and left it. My car runs great, 29 mpg, pulls like a mofo so I will just have to live without the loud PSHHHHT. I get a little blow off over 8lbs of boost(not near as loud as the 18g though), less than that I will have to just milk it and not spool at all or else I get surge.
Good luck 2 ya!

blcknspo0ln · Jul 19, 2005

droptopgst said:
I had the same problem with mine when I put my 50 on. No clue what the problem is I got sick of trying to find it and left it. My car runs great, 29 mpg, pulls like a mofo so I will just have to live without the loud PSHHHHT. I get a little blow off over 8lbs of boost(not near as loud as the 18g though), less than that I will have to just milk it and not spool at all or else I get surge.
Good luck 2 ya!

i'm at that point too. I can live without the blow off.. now onto turning hte boost up

droptopgst · Aug 15, 2005

alright man I got my BOV to work right again. Check for boost leaks. I had a bad injector seal which would leak a lot of air fast. do a psi test and make sure it holds 20 psi for a good 15-20 seconds, if not find your leak. I fixed this seal and now my bov is back to normal. after you do your test then tune good and mess around with the bov. this worked for me, hope it does the same 4 u!

blcknspo0ln · Aug 18, 2005

thanks for the tip.. it seems like my car has a major boostleak around the TB area [ can't figure out where ( new shaft seals, new gaskets + RTV, proper torque ).. so i'm at a loss right now

droptopgst · Aug 18, 2005

Like I said mine was at injector 4. Big Azz leak. try doing a compression test, put about 20-25 psi into it and poor some soap and water over it. I used a cup of water and just put a few table spoons of dish soap in it. You will see every area thats leaking. Fix all of those and you should be all set. O another thing is you might want to use a compressor to do this. It will get it up to 20 psi and the leak will be more noticeable than it would with a slow psi pushing bike pump.

The Central Hub for DSM Community and Information

NEED HELP: BOV stopped "working"

blcknspo0ln

92awddsm

dremersvision

marcmsj

blcknspo0ln

marcmsj

blcknspo0ln

marcmsj

blcknspo0ln

PieEyedPiper

washed_up_talon

fostytou

blcknspo0ln

Shadowofoblivio

blcknspo0ln

Patterson

Zexell

droptopgst

blcknspo0ln

droptopgst

blcknspo0ln

droptopgst

Similar threads

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds