[BMW GENIUS]

I just installed my BMS Stage 1 recently and I noticed if I go WOT @ 1600 RPM in 5th gear (6MT), I hear the turbo flutter and I wasn't sure if it's supposed to be doing that? I have heard that the flutter sound is due to compressional surge which is detrimental to the turbo and engine? Please tell me I'm wrong! I hope I am

[Daleb]

I have also got the same symptoms as yourself.

My initial thoughts were wastegate rattle as I also have the wastegate rattle on cold start if I hover the revs just above idle.

However this disappears as soon as the cold start finishes, so I'm starting to think it isn't this. Hopefully like yourself it isn't something serious.

I'm sure someone else can chime in

[horsepower_and_hounds]

I hear a lot more turbo whoooosh as it surges

[BMW GENIUS]

Originally Posted by ehagerty

I hear a lot more turbo whoooosh as it surges

But you don't hear any flutter? I also forgot to say that I also have the aFe Momentum Intake as well.

[ocN55]

I only heard a flutter after I installed my bms intake

[Daleb]

I will only hear any flutter if my windows are up and my ac/music are turned off. Basically has to be very quiet and at lower speeds of around 30/40mph.

[kerm1t]

you shouldn't hear any flutter. Compression surge is not good for your turbo. When i had jb4 and bms intake, it was a clean swoosh. i feel like some people here might be getting the term flutter mixed up

[Daleb]

Originally Posted by kerm1t

you shouldn't hear any flutter. Compression surge is not good for your turbo. When i had jb4 and bms intake, it was a clean swoosh. i feel like some people here might be getting the term flutter mixed up

Yes flutter may not be the best way to describe it, a constant pulsating sound between 1500-2000rpm maybe describes it better perhaps.

I'm going to run my car on map 1 and and 4 to see if the noise is still there using these

[Silvermike]

Originally Posted by Daleb

Yes flutter may not be the best way to describe it, a constant pulsating sound between 1500-2000rpm maybe describes it better perhaps.

I'm going to run my car on map 1 and and 4 to see if the noise is still there using these

maybe thats the EWG in action?

I kno i got a similar sound with my grimspeed boost solenoid on my evo.

[kerm1t]

Originally Posted by Silvermike

maybe thats the EWG in action?

I kno i got a similar sound with my grimspeed boost solenoid on my evo.

you should avoid anything that causes your turbo to flutter

[kerm1t]

Originally Posted by Daleb

Yes flutter may not be the best way to describe it, a constant pulsating sound between 1500-2000rpm maybe describes it better perhaps.

I'm going to run my car on map 1 and and 4 to see if the noise is still there using these

does it sound like this at low rpm?

[Silvermike]

Originally Posted by kerm1t

you should avoid anything that causes your turbo to flutter

A boost solenoid/ EWG flicking on and off isnt flutter. U hear it as the turbo is building boost and the solenoid comes on to control the spool. but it does sound a bit like flutter due to a bad dv.

[Daleb]

Originally Posted by kerm1t

does it sound like this at low rpm?

No it's during heavy throttle prior to the car dumping.

Sequence of events:

1500-2000rpm, heavy throttle and pulsating sound, lift off or less throttle then the bov will dump/vent

[Daleb]

Originally Posted by Silvermike

maybe thats the EWG in action?

I kno i got a similar sound with my grimspeed boost solenoid on my evo.

Originally Posted by Silvermike

A boost solenoid/ EWG flicking on and off isnt flutter. U hear it as the turbo is building boost and the solenoid comes on to control the spool. but it does sound a bit like flutter due to a bad dv.

Sorry I thought I had already replied to you. I'm starting to think it is the ewg in action.

Due to my daily driving habits my ff and avg ign values increase which mean I hit psi values above my target. Maybe the ewg is working a bit harder trying to keep me around my boost targets?

I'm not sure if BMW GENIUS is getting the same thing but the more I think about it the less worried I am. My logs were checked over by Russell at BMS and everything was fine.

[Daleb]

I've just taken this video, it might be hard to make out as its really faint in person. Actually sounds more like chatter in the video.

It happens around 2-3 second in then again at 10-11 seconds.

[2msport]

Originally Posted by Daleb

I've just taken this video, it might be hard to make out as its really faint in person. Actually sounds more like chatter in the video.

It happens around 2-3 second in then again at 10-11 seconds.

I can just make out the sound with my exquisite earphones... I think the N20 makes a similar sound. No idea what it is but I have a feeling its normal. Kind of sounds like its building pressure or pushing air through something and it does it at a weird frequency. I believe I've noticed it on my 28.

[Daleb]

Originally Posted by 2msport

I can just make out the sound with my exquisite earphones... I think the N20 makes a similar sound. No idea what it is but I have a feeling its normal. Kind of sounds like its building pressure or pushing air through something and it does it at a weird frequency. I believe I've noticed it on my 28.

Yeah the idea of pushing air is a good way to describe the sound. I'm not going to worry about, hopefully it has helped the OP BMW GENIUS to.

[kerm1t]

i couldnt hear anything in the video except for a slight air sucking, hissing sound. hissing/spool is fine, just no flutter/compression surge.

[BMW GENIUS]

Sorry for the late replies but thanks for all the help! I asked all my fellow technicians at work and they said it should be fine!