[Mk2] [Turbo] half throttle turbo neighhhh

[androo007]

Hi there chaps,

Interesting one - I've noticed recently that when I'm accelerating in 2nd - 4th gear under partial throttle the turbo spooling sounds like it does something kinda weird. It sounds like the turbo noise is like..... A horse neighing or hitting a limoter .... Like

Pssssshhhh shh shh shh - the boost amount is halfway up the needle. If I go full throttle then no problem and the whoosh is smooth again. Power delivery also smoother.

Any ideas? Cheers!

[dansREV2turbo]

Running a stock bpv and aftermarket air filter by any chance?

[androo007]

Nope stock airbox! Just a bov and exhaust. Rev 3

[Ryan S]

sounds like the BOV opening slightly when it's between vacuum and pressure, I've had this with many BOVs in the past, nothing to worry about, as long as it's closed on WOT

[androo007]

Oh really? Its halfway up the boost bar though pal, about 5psi I'd guess? Deffo not on the boundry! The fluttery sound sounds like it's the air rushing through the pipes rather than the bov itself if that makes sense?

[jon]

Probably a small hole in the BOV diaphragm.

[Ryan S]

Oh really? Its halfway up the boost bar though pal, about 5psi I'd guess? Deffo not on the boundry! The fluttery sound sounds like it's the air rushing through the pipes rather than the bov itself if that makes sense?

Take a video and post it up, from your description it deffo sounds like what i've said, what kind of bov is it? Just for reference i've managed this with my greddy type s, hks ssqv, apexi twin chamber, stock toyota valve, baileys and a whole heap of cheap nasty ones,

[Ryan S]

The hks gives a definite horsey type noise

[androo007]

Ok will do thanks matey. The power feels a bit odd too.....like juddery. I didnt think a bov would do that! It's only minor but I like my cars perfect

Genuine HKS Bov

[Ryan S]

Ok will do thanks matey. The power feels a bit odd too.....like juddery. I didnt think a bov would do that! It's only minor but I like my cars perfect

Genuine HKS Bov

hang on, you've changed the goal posts now haha, the car is also feeling juddery?? could be more to it then man,

I thought it was an HKS when you said "neighing" build boost and slowly lift off, you'll get the same noise

if your car's a rev2 you could quite easily get a bit of judder with a BOV, they are funny with which ones work and which don't. apei twin chamber made mine run like a dog. the best one was the baileys, felt exactly like stock. if it's a rev3 i can;t explain

[androo007]

Yeah man its a rev 3. Sorry I guess I'm not clear, kinda juddery, kinda like flat spot like.....

Its really hard to describe! I'll get a video up tomorrow and hopefully that'll help. Thanks chap!

[Ryan S]

Yeah man its a rev 3. Sorry I guess I'm not clear, kinda juddery, kinda like flat spot like.....

Its really hard to describe! I'll get a video up tomorrow and hopefully that'll help. Thanks chap!

hmmm, possible the bov opening under boost, do you have the stock one? or another one, worth changing even if just to rule out a fault bov

[Al-sw20]

Take the BOV out and blank it up.

[nbvolks]

Mine does the same under those conditions. Gen 2 motor with stock ct26 and an ARC induction box.

[2mad]

Hi there chaps,

Interesting one - I've noticed recently that when I'm accelerating in 2nd - 4th gear under partial throttle the turbo spooling sounds like it does something kinda weird. It sounds like the turbo noise is like..... A horse neighing or hitting a limoter .... Like

Pssssshhhh shh shh shh - the boost amount is halfway up the needle. If I go full throttle then no problem and the whoosh is smooth again. Power delivery also smoother.

Any ideas? Cheers!

Split boost hose .. loose hose clamp maybe

[2mad]

How did you get on , this was a new one on me , love to know what the problem was for future reference .

[androo007]

Hey guys tried to video today but the turbo induction noise didnt come out on the video! Will be capturing in the morning.

I have noticed though, under 75% throttle in 3rd gear (as an example) it'll boost, and then drop a little before settling without me adjusting the pedal. Normal or boost leak?

[2mad]

Turbo problems .. check 3 things..


1, induction .. is you air filter / air box doing what it should.

2. forced induction .. do you have a boost leak.

3. power .. is the turbine getting what it needs .. clogged cat can mess with things.


4 .. Check the compressor wheel and turbine are ok , with not to much play.


Best of luck bud

[nbvolks]

Here's mine making the sound I think you're talking about.

http://youtu.be/gmLf33FoEnk

[Ryan S]

100% your bov matey, i can make mine do this noise by lifting off slowly, sounds identical, the question is really, is it doing it when it's supposed to? If it's holding boost with wide open throttle then it's no issue