M35 Strange Exhaust Noise

[fezmo]

HI there,

My stagea has started making a really strange noise through the exhaust. It only happens around full boost when it's about to shift gears (rarely from 1st to 2nd though) it's a low pitched rolling noise (fart) and if you feather the throttle it will maintain the noise until it shifts.

It sounds really wrong!

Getting a dump pipe, front pipe and high flow cat fitted tomorrow, so I might get a look when it's on the hoist.

Any ideas?

[zei20l]

stock exhaust??

if it is, mine does it too. i THINK there is a leak or blockage somewhere. it will all go in the next few months..........

[iamhe77]

Yep. Mine did it to.

Try tightening the turbo -> dump bolts. Worked for me

[fezmo]

stock exhaust??

if it is, mine does it too. i THINK there is a leak or blockage somewhere. it will all go in the next few months..........

I have a fujitsubo legalis, but everything from the turbo to the cat is stock (til tomorrow anyway )

Hopefully I can sort it out tomorrow, was just checking it might not be anything else.

[michaelcoota]

Interesting, I get what I thought was a low pitched vibration/groan that I thought was some sort of induction noise, worse when the access plate for the airbox is removed and a k&N in there, not sure if its the same thing or not?

[Cephas]

Interesting, I get what I thought was a low pitched vibration/groan that I thought was some sort of induction noise, worse when the access plate for the airbox is removed and a k&N in there, not sure if its the same thing or not?

I need to do some investigation around this as well.

Not sure if the K&N panel filter is giving more induction noise, or if I have wheel bearing on the way out.

[fezmo]

just a little update,

had the dump and new front pipe fitted at Westside, so everything was tightened up around there and I'm still getting the noise. Nice increase in power though, feels pretty good through the mid range.

Dropped it off to Ben at Northshore today & he thinks it's a blow off problem, so he's ordering a new one ($250?)

Hope this can get it sorted!

[andy65b]

just a little update,

had the dump and new front pipe fitted at Westside, so everything was tightened up around there and I'm still getting the noise. Nice increase in power though, feels pretty good through the mid range.

Dropped it off to Ben at Northshore today & he thinks it's a blow off problem, so he's ordering a new one ($250?)

Hope this can get it sorted!

Do you know what boost you are getting when you hear this noise?

I ask as I have had a strange noise and it tuned out to be the Wastegate sticking open and this increased the noise at the turbo. The cause turned out to be the solenoid sticking and this kept the wastegate open.

The result is you only have a max of 9psi when this happens.

In my case it was fixed by stopping and turn off the ingnition and problem fixed , till the next time.

Seemed to occur when under full throttle for more than 5-10 seconds.

Cheers

Andy

[fezmo]

Do you know what boost you are getting when you hear this noise?

I ask as I have had a strange noise and it tuned out to be the Wastegate sticking open and this increased the noise at the turbo. The cause turned out to be the solenoid sticking and this kept the wastegate open.

The result is you only have a max of 9psi when this happens.

In my case it was fixed by stopping and turn off the ingnition and problem fixed , till the next time.

Seemed to occur when under full throttle for more than 5-10 seconds.

Cheers

Andy

Not sure what boost I'm getting, only have the factory gauge and haven't done the solder fix on the sender unit yet. It happens pretty erratically though, if it happens I can still get what "feels like" full boost the next time i'm accelerating hard i.e 2mins later.

Thanks,

Will

[iamhe77]

Exhaust manifold to turbo flange may be leaking?

Mine is making that sound again and it certainly isn't any join from the back from the turbo down to the muffler.

[andy65b]

Not sure what boost I'm getting, only have the factory gauge and haven't done the solder fix on the sender unit yet. It happens pretty erratically though, if it happens I can still get what "feels like" full boost the next time i'm accelerating hard i.e 2mins later.

Thanks,

Will

Just spoke to Ben and it sounds like a different problem.

Cheers

Andy

[fezmo]

Exhaust manifold to turbo flange may be leaking?

Mine is making that sound again and it certainly isn't any join from the back from the turbo down to the muffler.

Thanks,

Haven't got the car with me today, can you access this from the top of the engine or do you need it up on a hoist?

[Jetwreck]

Hope for your sake it's not the turbo. mine was doing a farting too!....not anymore though....new turbo!

[Angus Smart]

Nice, Brad would have loved working on another m35 at westside!!

[StefanNM35]

hi all,

my '01 Stagea used to do it also, it would do it at about 3500rpm, 1st, 2nd and sometimes third but only if i eased up to half throttle, if i kept it flat it would only happend in 3rd most of the time.

what worked for me was swapping the factory BOV with an aftermarket (turbosmart) BOV i got from a mate from his R33. just to test it, i did swap it back to factory a couple of weeks later and it started making the noise again. so now i'm driving around with a turbosmart BOV.

hope its the same noise, on mine the noise was coming from the drivers side and sometimes i could feel the vibration in the gas pedal.

hope your problem is as easy as mine was.

Stefan

[fezmo]

yep, it's the BOV

ordering one through Ben and it should be all sorted. He's got a really nice black ARX in there, kinda wish I'd gone for one originally, the extra ride height would be nice......

[Bis-e Bee]

hi all,

my '01 Stagea used to do it also, it would do it at about 3500rpm, 1st, 2nd and sometimes third but only if i eased up to half throttle, if i kept it flat it would only happend in 3rd most of the time.

what worked for me was swapping the factory BOV with an aftermarket (turbosmart) BOV i got from a mate from his R33. just to test it, i did swap it back to factory a couple of weeks later and it started making the noise again. so now i'm driving around with a turbosmart BOV.

hope its the same noise, on mine the noise was coming from the drivers side and sometimes i could feel the vibration in the gas pedal.

hope your problem is as easy as mine was.

Stefan

I was looking at Turbosmart BOV's and will probably have one fitted when the turbo and dump are upgraded. Out of interest, do you know what model of Turbosmart you put on? I've been in touch with Turbosmart and they have recommended the dual port.

yep, it's the BOV

ordering one through Ben and it should be all sorted. He's got a really nice black ARX in there, kinda wish I'd gone for one originally, the extra ride height would be nice......

Ride height is for pansies!! (he says as he scrapes on everything lol)

[iamhe77]

Ride height is for pansies!! (he says as he scrapes on everything lol)

and bitching about scraping can easily be stopped.... I will swap you my spare OEM suspension for your Nismo S-tune.

See? Pissing and moaning easily averted mate

[Bis-e Bee]

and bitching about scraping can easily be stopped.... I will swap you my spare OEM suspension for your Nismo S-tune.

See? Pissing and moaning easily averted mate

Sorry, Iain already has dibs on the s-tune and everything else on my car lol

I don't think I want to drive a boat so for now I'll keep the suspension as it is

[bbenny]

Yeah I would be interested to see if a BOV does fix this, because I have noticed it starting on my car since doing the cat back - so increased boost could cause the sound if its BOV related.

My brothers M35 makes the exact same noise as mine. Usually in 2nd or 3rd at 3500-4000rpm (which is when my car makes max boost according to my El boost guage)

Let me know what BOV you guys use, and if its a direct bolt on or needs some adaptors etc.