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Hey all,

my turbo has started making these wierd noise, mind you only on the dyno under full load in 4th. Its like a loud trumpet sound.

We tried to look for any lose clamps for an air leak. couldnt find anything. Pulled off intake piping and realised the turbo had shit in it and has a bit of shaft play.

Still made the power though so dont know if the turbo is on its way out or something else?

Vid

any help would be appreciated

cheers :)

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whatever it is, its coming from the wastegate or when the wastegate opens

if you hear the engine you can it ramp on boost and once what i would call peak boost is made, shortly after you get that wierd whining sound

id say its something on the wastegate or the boost control system (that opens when peak boost is reached)

In a roller bearing system the balls are the centripetal support as well as the rolling object. They are also made in a harder material then the bearing cages which they run on. Then is worn the rotor assembly looses its support and vibrates. That causes this noise, as well as having wheels rubbing against housings. The clearance in a ball bearing rotor should be no more then 10thous. If it feels like there is a “bit of play" then it is dead. Depending on how bad it is, it can still make power, how ever it will be substantially less then when it is good, it will also becomes noticeably laggier.

Obviously check for gaskets and what ever leaks and hopefully that is the cause.

im pretty sure its the turbo, but there is 2% chance it could be a split hose we could not get too. :down:

A hose clamp was left off the intake pipe and it ingested a shiteload of debris, 2mm thick around inducer.

front wheel has a little play which is why i supsect turbo....

on this topic. what usually happens when a turbo finally dies from bearing falure? do wheels often fly off or do they just get real noisey and inefficient? my gt30's starting to make a bit of noise, kinda gay considering it only has 10k km's on it....

So many of these threads end up being manifold gasket or turbo manifold gasket leaks or split or leaking hoses that I would still be looking very carefully in this direction.

I had a tiny leak from external gate/exhaust gasket that whistled really slightly that I finally fixed recently.

The play in the turbo isn't a great sign but common things occur commonly.

All good. I'll change it when it shits itself :) lol

do a full throttle accel run next time its cold (one run when its cold wont hurt) see if noise changes pitch, if so it could be turbo to manifold leak. or listen for slight chug from turbo area with it idling cold..

do a full throttle accel run next time its cold (one run when its cold wont hurt) see if noise changes pitch, if so it could be turbo to manifold leak. or listen for slight chug from turbo area with it idling cold..

Will do Trent. Got a freeway near my place so can test full throttle 3rd and see what happens. I'll let you know what happens

When we were at Winton for Nats, everytime you came up the spectator straight we were all like :huh::huh: Wtffff is that? But without knowing what mods you had done I had no idea if it was meant to sound like that, lol

  • 2 months later...

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