BOV flutter since FMIC install

[doug]

I've now tried three different BOVs since my new FMIC went in, and they all flutter like a flock of pigeons-- a crushed 1G, an uncrushed 1G both with and without the Dejon stop leak kit, and now most recently a Monza SSQV (the "fake" HKS). Could there be something else besides the BOVs at fault? Maybe the piping leading to the BOV flange needs smoothing out or something? I mean, when a bone stock uncrushed 1G BOV flutters, I would think something has to be wrong-- it didn't seem to do that before the FMIC.

 

[Turbo Talon DL]

My uncrushed 1g BOV flutters too. When it opens, it flutters once like its on its way open, then gets progressively quiet, but only under full boost (10psi if you wanna call it full boost) The first time I heard it do that, it kinda tripped me out too. Even with it recirculated, its still pretty loud. You can hear the echo off the car next over.

 

[hewhoisknot]

u put the line on the right nipple?

 

[doug]

There's only one nipple on the 1G and HKS-style BOVs.

 

[gas_man]

My 1g and Greddy type s did it after my fmic install too. I found I had some boost leaks and that helped the fluttering alot but it didn't totally go away.

 

[doug]

Hmm, interesting. I leak-tested mine right after the FMIC install and fixed all but one (TB shaft seals), but that hasn't seemed to help.

 

[matt97gst]

Ever fix this doug?

 

[teevee]

Try a new gasket, I had to get a new one when I did my fmic install and it helped.

 

[doug]

Problem still exists. I'm still using the HKS-style BOV on there now. Some have suggested that the problem is too much air trying to exit the BOV, causing surge.

I may try a new gasket, but I know it's not leaking from there because I've done several boost leak tests since the install. Thanks to everybody for the input so far.

 

[danielbui]

try running your BOV vacuum line by itself to the factory BOV vacuum line nipple off the manifold. i had the same problem and thought of a million things that were wrong and came with one idea that later worked. i had my manual boost controller hooked in line with my BOV line. i later removed the boost controller vacuum line and t-ed it with my boost gauge line and my FPR line and kept the BOV isolated from any other vacuum source and it fixed my problem. weird though all my 1G friends never had this problem. hope that helps good luck.

 

[doug]

Thanks for the idea, but my BOV is already routed like that. I never liked the idea of running the MBC off the BOV line.

 

[danielbui]

your BOV's rerouted still? i noticed with some bov's rerouted, they sounded alot different than vented. block off the recirculation part of your intake, and see what it sounds like vented. i know its a no no but hey you never know. if its vented nevermind, i am out of clues.

 

[doug]

Yes, my BOV is recirculated. I did try venting it, but the flutter remained.

I will eventually try the Forge BOV, I think. I'll just live with it like it is for now.

 

[Skunked tsi]

How many pounds of boost are you runnign and what turbo? Mine does this aswell if i run less then 18psi, does a lil pffffffffffff ffff f fff f f f f thing. When I run 25 like I do daily I have no issues. I dont see it being a problem just maybe an annoyance I wouldnt worry about it like you are if three bovs are having the issue its not the bov, I would assume.
Tyler

 

[94Jettameowpsst]

It could just be from the pressure drop goin from a smic to a fmic.

 

[cs82685]

How many pounds of boost are you runnign and what turbo? Mine does this aswell if i run less then 18psi, does a lil pffffffffffff ffff f fff f f f f thing. When I run 25 like I do daily I have no issues. I dont see it being a problem just maybe an annoyance I wouldnt worry about it like you are if three bovs are having the issue its not the bov, I would assume.
Tyler

^^^that's nice to hear, b/c mine flutters most of the time, once in a blue moon it will sound proper for a few minutes and then back to fluttering, but i'm only hitting like 5.5psi (rs-t) so i guess i'm not gonna worry about it, it just makes me hope its not messing up my turbo from compressor surge

 

[doug]

How many pounds of boost are you runnign and what turbo?

20-21 PSI on a TD06 18G.

 

[doug]

It could just be from the pressure drop goin from a smic to a fmic.

Yep, that may be it.

 

[danielbui]

i took off my intake while i was dealing with some boost creep issues and left it off while i was doing some test runs and mine was doing some fluttering only at low boost as well (6-12psi). as soon as i put my intake back on i didn't hear any such fluttering. i tried to adjust until i didn't hear the flutter anymore but it didn't blow off at low boost only on high boost. a member on hear almostquick has a RFL from Turbo XS and his does the exact same but then again he also runs without an intake.

 

[gixrman]

20-21 PSI on a TD06 18G.

My TIAL does the same and the fix for it is to up the BOV spring pressure, running the same boost. Low boost flutter will not hurt anything.

 

[skinnykenny84]

I had the exact same problem on my old GST. I had a greddy type s and since it was adjustable I could "fine tune" it so to speak. If it was too tight it would flutter and all I had to do was loosen the set screw on top and it would slowly fade away. It seems that you dont mind trying diff bov's; I would just about gaurrentee the flutter would be gone if try that bov.



hell someone might even trade you on this site

 

[skinnykenny84]

I might have said that backwards.... maybe when you loosen it it got better

 

[SpoOLxExO]

I've now tried three different BOVs since my new FMIC went in, and they all flutter like a flock of pigeons-- a crushed 1G, an uncrushed 1G both with and without the Dejon stop leak kit, and now most recently a Monza SSQV (the "fake" HKS). Could there be something else besides the BOVs at fault? Maybe the piping leading to the BOV flange needs smoothing out or something? I mean, when a bone stock uncrushed 1G BOV flutters, I would think something has to be wrong-- it didn't seem to do that before the FMIC.

Awwww for christ sakes, its compressor "Surge". You should know this doug.

http://www.dsmtuners.com/forums/showthread.php?t=201608

Lower BOV Spring tention band aids this situation, but not a fix for High boost levels.

Things to check since your FMIC install:

1. Boost leaks, any at all? Compressor flange ,unless it doesnt have one.

2. What did you change during the install, as far as what you touched during it?

3. What type of core is it?

4. Check for obstructions in the charge piping?

Look at these things and get back to the board!

 

[doug]

1. Boost leaks, any at all? Compressor flange ,unless it doesnt have one.

2. What did you change during the install, as far as what you touched during it?

3. What type of core is it?

4. Check for obstructions in the charge piping?

1. I did have on in the throttle body (seals), but I've now replaced it. One more popped up during the last boost leak test (somewhere in the IC piping), so I'll be fixing that one shortly.

2. Besides the obvious (core, piping) the only other thing changed was the addition of a tranny cooler (it's an A/T).

3. Spearco 2-216 core from DV/DT Fabrications. I have a Tech Article covering the install but I'm too lazy to find the link to it.

4. I checked before the install, but not since. When I go to track down that last boost leak, I'll probably remove each section of piping to check.

Thanks for the list. And OK, it's surge.