[Mk2] [Turbo] Strange "woof" noise on oem valve activating

[sconisbee]

Can anyone help.

I've got pretty much a standard setup on my Rev3 Tubby.

New turbo about 3 years ago and HKS induction kit. Apart from that, totally standard.

When the OEM BOV operates occasionally I get a strange "woof" kind of sound.

Hard to describe but needless to say it's annoying. Anyone else ever had this or have any idea what it might be?

Cheers
Steve

[Ian Geary]

I get this too - noticed it immediately after switching an oem unit back from my former SSQV.

it was off ebay, so the OE valve could be knackered for all I know.

Was told to look for loose pipes, but it still isn't sorted.

The unit is essentially one big valve, so it can only be caused by the valve moving back and forth. I keep meaning to take the tubing off and lubricate it.

Ian

[oBladeo]

I have a standard one somewhere you can have for £5 plus p&p

I'll try and find it tonight if you want it

[sconisbee]

Yeah maybe, have a look and see if you can find it. I have just bought one from someone else on imoc and tried that and it does the same thing, but thats not to say that it worked properly in the first place. Take a look and see if you can find it and I'll have a think about it.

The only reason I went back to the standard BOV was because when I put a VTA valve on I was only getting about 50% boost. I'd rather have the car moving properly and not making a sound!

[oBladeo]

Very strange i've hurd of people with BOV issues on the rev1 (non standard BOV) but not a rev 3 that that often.

I have a rev 1 and have a hks and works fine for me

I'll let you know later

[SW20Paul]

Does it sound like a bit like a goose honk.

[2Crooky]

Welcome to the world of turbo farting!!

When fitting an aftermarket induction kit/air filter it causes some sort of surge in the stock BOV and you get the "goose honk" as mentioned above

Nothing to worry about...

[Tom Solan]

Hi guys,

It's nothing to do with BOVs'. It's the air induction kits that do it. I get it on virtually every car with an a/am air kit and even those with no a/m BOV

Tom
NVI

[SW20Paul]

Hi guys,

It's nothing to do with BOVs'. It's the air induction kits that do it. I get it on virtually every car with an a/am air kit and even those with no a/m BOV

Tom
NVI

Im pretty sure it is the bov that makes the goose honk if you change the bov for another type it goes away its just the way the OEM bov works.

[DannyW]

Hi guys,

It's nothing to do with BOVs'. It's the air induction kits that do it. I get it on virtually every car with an a/am air kit and even those with no a/m BOV

Tom
NVI

WRONG!

It's the BOV making the sound (OEM or otherwise), it's just heard easier through an induction kit that's all.

[mattcambs]

My stock BOV honks/gulps/farts whatever you want to call it. I think Tom is right to a certina extent in that the noise is a result of the re-circed air building up in the intake pipe and being audible through the air filter.

As far as I know the stock airbox and resonator is designed to cancel the noise. Having driven my mate's totally Rev3 Turbo there is no noise at all. Mine has a ARC induction and some of the noises I get are hillarious. Somestimes a fart can last a few seconds on certain part throttle openings!

If you have a decent boost gauge you can see the pressure drop every time your BOV farts.

[sconisbee]

I suspected it was going to be something to do with the Induction Kit as it does make all turbo noises much louder. Not really sure what to do now as the noise is horrible. It goes away if I stick an aftermarket VTA valve on, but then the car doesn't go properly. Mind you, thats sticking a valve in the front most intercooler pipe. Is it worth trying on the cold side? Or maybe even saucing an aftermarket recirc valve?

Can you get a bolt on replacement for the MR2 to avoid cutting pipes?

[oBladeo]

aaa good job i forgot to look last night lol

What after market BOV did you have before? (hks sqv?, bailey's?, so on)

[sconisbee]

It was a cheap nasty no-name job. Worked OK in a different car though. Just bidding on a Blitz ssq on ebay at the moment. Don't suppose anyone else has got one they would be willing to part with for some small amount of cash? Or, even better still, someone in my local area that would be willing to lend me one on good faith to test. Outside chance of that I know but if you don't ask.....

[oBladeo]

I'm running a hks sqv atm with no probs but then again before that i had the bailey's and had no problems.

If the valve is second hand make sure you don't need to refurb it as they wear out after a while

[luthor1]

hehe - yeah I get the "HaaaaaRRRRRNNNK" noise too, usually during static throttle position but with the turbo/BOV/everything sorting itself out.

I spent AGES going round the car making sure it had no leaks, now I just scare new passengers with it "what's that WHAT'S THAT!!" I just tell them it's digesting small children

[Caribbean_Blue]

Perfectly normal. Standard BOV with aftermarket Induction kit will make/allow a more vocal 'woof' noise as it is discribed.

The induction kit kind of acts like a megafone amplifying the sound thats it.

[SW20Paul]

I suspected it was going to be something to do with the Induction Kit as it does make all turbo noises much louder. Not really sure what to do now as the noise is horrible. It goes away if I stick an aftermarket VTA valve on, but then the car doesn't go properly. Mind you, thats sticking a valve in the front most intercooler pipe. Is it worth trying on the cold side? Or maybe even saucing an aftermarket recirc valve?

Can you get a bolt on replacement for the MR2 to avoid cutting pipes?

Just vent the stock BOV if you want rid off the noise, Just pull the re-circ pipe off and block it off so you dont suck in unfiltered air ( I use a coke bottle top or sawn down broom handle)

The OEM BOV is really loud aswell

[sconisbee]

Sorted. Recirc pipe off, works a treat. Nice sound and the car works properly! Great advice, ta