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Compressor Surge??

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Chumpaumpalumpa

Proven Member
1,554
303
Jun 16, 2014
La Habra, California
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so I have been reading up on compressor surge and am getting nervous that my car has it. I have a recirculated BOV and this happens every time I let off the throttle above 0 psi.... The more boost the louder the sound. Is this compressor surge or something else. Sorry about the wind noise! Oh also, it does NOT make that low pitched barking noise typically associated with surge. Am I safe?
 
Not surge, sound like the bov is set too tight (if adjustable) or isn't pulling open.
 
I believe it is.... The make is unknown as its been on the car since I bought it and everything that was some extravagant color was painted matte black for a stock look. But there is a bolt coming out of the top so it might be... If it's too tight could that potentially cause compressor surge? Also y is it so damn loud even tho it's recirculated? Does that just mean it's hooked up wrong?
 
What kind of BOV is it? It sounds like it is misadjusted or that it is not opening at all.
 
If it has an adjustment screw on top, turn it out half a turn at a time and test in between to see if the sound goes away. Also get a pic of it. The BOVs that I know of with a screw on top are usually the Greddy or Greddy style knockoffs.
 
these good enough?
 

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Definitely not compressor surge. The bad comp surge happens while you're in the throttle still, not after you lift.

It sounds to me like the vacuum line might not be hooked up to the right port on that CBV. Were any changes made to the car in between when the CBV didn't sound like this and when it started sounding like this? I know, even with experience, it's sometimes easy to overlook something small like a vacuum line.

Good luck and post back here with your results in case anyone searches this thread in the future.
 
Definitely not compressor surge. The bad comp surge happens while you're in the throttle still, not after you lift.

It sounds to me like the vacuum line might not be hooked up to the right port on that CBV. Were any changes made to the car in between when the CBV didn't sound like this and when it started sounding like this? I know, even with experience, it's sometimes easy to overlook something small like a vacuum line.

Good luck and post back here with your results in case anyone searches this thread in the future.
give this man a cookie! upon further inspection, he is exactly correct. I was just getting ready to post that information. Anyways, the vacuum line has not been hooked up since i bought the car. only problem is that i dont see anywhere to hook it up to. Any ideas?[DOUBLEPOST=1418054297][/DOUBLEPOST]Is it that spot under the #3 injector harness?[DOUBLEPOST=1418056496][/DOUBLEPOST]So that bottom nipple needs to go to
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the nipple above runner #2?
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I'm glad I was able to help. The reason it sounded like it was still blowing off but struggling with it was because it was enough boost to push the spring open when normally there is vacuum assistance on the diaphragm to lift the valve open. You were fighting against what the vacuum assisted system does in this application.

Glad you got it figured out. The top port on the BOV is the one you want to use because you're applying boost on top of the diaphragm to keep your valve from opening while you're in boost, and once the plate closes, vacuum is introduced to the top of the diaphragm, assisting it in opening.
 
I'm glad I was able to help. The reason it sounded like it was still blowing off but struggling with it was because it was enough boost to push the spring open when normally there is vacuum assistance on the diaphragm to lift the valve open. You were fighting against what the vacuum assisted system does in this application.

Glad you got it figured out. The top port on the BOV is the one you want to use because you're applying boost on top of the diaphragm to keep your valve from opening while you're in boost, and once the plate closes, vacuum is introduced to the top of the diaphragm, assisting it in opening.
I actually haven't got it figured out, I was wrong about the issue, as i thought I needed to hook up the bottom line as well. http://www.dsmtuners.com/threads/bov-vacuum-line-confirmation.488147/#post-153482316
This is where I am now.
 
as i thought I needed to hook up the bottom line as well

In that thread everyone told you don't need to hook up bottom one. Hook the top one to the manifold and if it still doesn't work adjust it (if you even can with that bolt in it) if it still doesn't work take it apart and and make sure everything looks ok inside or replace it with a 1g BOV or something else that works instead of that ebay knock off.
 
In that thread everyone told you don't need to hook up bottom one. Hook the top one to the manifold and if it still doesn't work adjust it (if you even can with that bolt in it) if it still doesn't work take it apart and and make sure everything looks ok inside or replace it with a 1g BOV or something else that works instead of that ebay knock off.
thanks for the advice. ill try adjusting it tomorrow and post the results. I need to turn the bolt to the right to tighten it and hopefully solve my problem, correct?
 
I have the actual Greddy version of this. Mine did the exact same thing(unless your doing full throttle pulls) Mine had 2 springs on the inside to hold the diaphragm down I had to remove a spring and adjust from there. They say that hooking the bottom nipple up will work also, it gets a boost source from before the throttle body close as you can to the turbo.
 
I have the actual Greddy version of this. Mine did the exact same thing(unless your doing full throttle pulls) Mine had 2 springs on the inside to hold the diaphragm down I had to remove a spring and adjust from there. They say that hooking the bottom nipple up will work also, it gets a boost source from before the throttle body close as you can to the turbo.
Thanks for the input. So I am loosening it or tightening it then? I believe loosening it will fix it, since it is "softening" the spring correct? I am still confused as to what exactly the bottom one does, and more importantly to me, where the air is going that it is sucking in. :hmm::confused:
 
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ok so i fiddled with the screw....... and nothing...... i mean i could feel the screw getting tighter or loser, but te sound and effect did not change at all so now i am :confused:
 
The air isn't going anywhere usually. Maybe you valve is staying open under vacuum or light load. It sounds like you need to disassemble your bov and see if its damaged or swap on another and see if that fixes your issues. People have suggested this stuff many times, but you only seem to hear what you want. Eventually people wont take you serious and stop trying to help. You are posting about this problem in 2 threads right now for christs sake. This is the kind of problem most people wouldn't even bother to start a new post about. It has been covered 100's of times and a simple search could have given you all the knowledge and information you needed to solve the problem in 10 minutes. Whatever is wrong, it is not a complex problem.
 
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