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Old 12-28-2012, 11:59 AM   #1
Suspence
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Default Flutter under boost?

I have been experiencing a bit of Turbo flutter when I'm in boost, i've heard it about three times since I last had my car tuned with a few parts installed. (DP, Headers, Exhaust). I figure that it's air being pushed back into the Turbo or maybe because I'm running a stock BOV? Not sure, still new to turbo vehicles.

Any help would be appreciated, need a solution so I don't damage anything.

Thanks,
-Spencer
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Old 12-28-2012, 12:04 PM   #2
Stoutjr
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Sounds like its letting out air at an early psi. May want to bring it up to the tuner that its letting out the boost to early.

I have this this same problem when I adjust my waste gate too low.
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Old 12-28-2012, 12:09 PM   #3
Suspence
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Quote:
Originally Posted by Stoutjr View Post
Sounds like its letting out air at an early psi. May want to bring it up to the tuner that its letting out the boost to early.

I have this this same problem when I adjust my waste gate too low.
Oh ok, got it. How bad of a problem is it to have? If I somewhat baby the car for a few weeks until I can get back to my tuner. I still have power, I just hear it and it doesn't sound too healthy.
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Old 12-28-2012, 12:20 PM   #4
The Duke
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Quote:
Originally Posted by Stoutjr View Post
Sounds like its letting out air at an early psi. May want to bring it up to the tuner that its letting out the boost to early.

I have this this same problem when I adjust my waste gate too low.
Or it's just the internal wastegate flapping around and doing it's job. Happens with intakes mostly, but downpipes can let enough sounds through to make it audible as well.

It's wastegate flutter. It's caused by the BCS system opening/closing the wastegate to modulate the boost pressure. In stock form, there's enough pipe mass/baffling so don't hear it. With aftermarket intakes, thinner wall/less restrictive pipes the sounds permeates more into the cabin. If anything the sounds is something you want to hear, as it means the system is doing it's job.

I'm going to take a guess it happens mostly at higher gears in lower rpms at full boost? Didn't really happen until you put the aftermarket parts on?
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Old 12-28-2012, 12:47 PM   #5
Suspence
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Quote:
Originally Posted by Stoutjr View Post
Sounds like its letting out air at an early psi. May want to bring it up to the tuner that its letting out the boost to early.

I have this this same problem when I adjust my waste gate too low.
Quote:
Originally Posted by The Duke View Post
Or it's just the internal wastegate flapping around and doing it's job. Happens with intakes mostly, but downpipes can let enough sounds through to make it audible as well.

It's wastegate flutter. It's caused by the BCS system opening/closing the wastegate to modulate the boost pressure. In stock form, there's enough pipe mass/baffling so don't hear it. With aftermarket intakes, thinner wall/less restrictive pipes the sounds permeates more into the cabin. If anything the sounds is something you want to hear, as it means the system is doing it's job.

I'm going to take a guess it happens mostly at higher gears in lower rpms at full boost? Didn't really happen until you put the aftermarket parts on?
Exactly.

It doesn't happen until 4-5kRPM, under a lot of throttle pressure. That's good to hear though, I just was hoping it wasn't doing any damage of any sort.

Thank you for the information.

-Spencer
Helps a lot!
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Old 12-28-2012, 01:28 PM   #6
RoadKillDMD
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Quote:
Originally Posted by The Duke View Post
Or it's just the internal wastegate flapping around and doing it's job. Happens with intakes mostly, but downpipes can let enough sounds through to make it audible as well.

It's wastegate flutter. It's caused by the BCS system opening/closing the wastegate to modulate the boost pressure. In stock form, there's enough pipe mass/baffling so don't hear it. With aftermarket intakes, thinner wall/less restrictive pipes the sounds permeates more into the cabin. If anything the sounds is something you want to hear, as it means the system is doing it's job.

I'm going to take a guess it happens mostly at higher gears in lower rpms at full boost? Didn't really happen until you put the aftermarket parts on?
+1 I agree with this ^^^

OP, to be safe, to you have an AP or other tuning software on you laptop, you should take a couple of data logs to check I'd things are running okay.

Quote:
Originally Posted by Stoutjr View Post
Sounds like its letting out air at an early psi. May want to bring it up to the tuner that its letting out the boost to early.

I have this this same problem when I adjust my waste gate too low.
Wut? Sounds like you're just talking out your arse... Don't spread useless misinformation. It makes you look really stupid
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Old 12-28-2012, 01:45 PM   #7
Stoutjr
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Lol just an observation, had this problem when I had an electronic boost controller freshly put on. Solved by changing BCS settings. Suppose I was a too vague. My bad
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Old 12-28-2012, 03:39 PM   #8
Half Crazed
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I have the same fluttering when I hit 17lbs.. but I'm aftermarket. Pretty sure it's normal so you don't blow your engine.
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Old 12-28-2012, 04:09 PM   #9
tuzzio
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It's the BCS opening and closing when you're at full boost.
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Old 12-28-2012, 10:12 PM   #10
hutch959
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at what rpm and throttle position? if is lower rpm at wot its more than likely turbo surge. ... like a "cha, cha,cha, cha" sound.
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