Turbo sounds like a super charger

The last two days my stock twins sounds like a super charger when its building up boost and then seems to lose pressure. The boost reading says it at 0.65 then it loses the pull.

Is this signs of the turbo going out? I've checked the Fumes from the exhaust and its fine no blue smoke or anything.

The last two days my stock twins sounds like a super charger when its building up boost and then seems to lose pressure. The boost reading says it at 0.65 then it loses the pull.

 

Is this signs of the turbo going out? I've checked the Fumes from the exhaust and its fine no blue smoke or anything.

If you go to this link http://www.mkiv.com/techarticles/index.html#other_mods scroll down a little bit and you can playback the infamous ''dead whine''.

Hope its not the same sound,

i don't think it sounds like that because the noises is constant. my one builds up if pressing half way down with the pedal around 2500rpm and the after a while you don't hear it.

My car makes this supercharger sound too and it fades out after 3,500 revs, could it be a boost leak?

My car makes this supercharger sound too and it fades out after 3,500 revs, could it be a boost leak?

exactly that! was yours just a leak then.?

I'm not sure bud, I'm just assuming? It can't be the dead wine as tests associated with the UK spec turbo's.

i would have a look at the turbo fins on the first turbo and i would bet they are missing the tips something like that

Mine is a UK spec turbo.

The sounds will pick then around 3500rpm you can't hear it spool and lose compression on each gear

My car makes this supercharger sound too and it fades out after 3,500 revs, could it be a boost leak?

Your car was fine when i drove it it pulled well and made no strange noises.

i have the same sorta sound, mine is a hissy whistle sound, as if air is leaking, no loss in performance though, and boosts fine. so i dont have boost leak, going to try vacuum leak next....

i have the same sorta sound, mine is a hissy whistle sound, as if air is leaking, no loss in performance though, and boosts fine. so i dont have boost leak, going to try vacuum leak next....

Just out of curiosity, do you reckon its a boost leak on mine because the lost of performance?

The best way to describe the sound it is it builds up then......the noise disappear, just want to make sure that this problem ain't nothing more than just a boost leak.

its hard to explain over the internet,

tbh i have a hissy whistling sound on mine that i didnt have before, but no loss in performance, just the sound.

that doesnt mean that I dont have a boost leak though, as the turbos could just be working extra hard to compensate for the leak.

have you done a boost leak test? (block the air filter off, and fill the intake manifold with air from a compressor, and put soapy bubbly water over the engine bay)

its hard to explain over the internet,

 

tbh i have a hissy whistling sound on mine that i didnt have before, but no loss in performance, just the sound.

 

that doesnt mean that I dont have a boost leak though, as the turbos could just be working extra hard to compensate for the leak.

 

have you done a boost leak test? (block the air filter off, and fill the intake manifold with air from a compressor, and put soapy bubbly water over the engine bay)

No i ain't tried the boost leak test yet. But to be honest i ain't really messed around with the intercooler pipes and im surprised i have this leak because the inertcooler system is less than a year old ...

If you arn't making stock boost check all the vac lines for splits and to make sure nothing has popped off. I am sure the first turbo make 0.65 the it goes to 0.8 when the second one comes online, I will wait to be corrected. Next thing would be to check all the VSV are working correctly but the increased noise makes me suspect a split pipe leaking boost somewhere.

If you arn't making stock boost check all the vac lines for splits and to make sure nothing has popped off. I am sure the first turbo make 0.65 the it goes to 0.8 when the second one comes online, I will wait to be corrected. Next thing would be to check all the VSV are working correctly but the increased noise makes me suspect a split pipe leaking boost somewhere.

my second turbo i think ain't even came on because i tend to lose pressure at 0.65. so that would be cause by a vacuum pipe ?

my second turbo i think ain't even came on because i tend to lose pressure at 0.65. so that would be cause by a vacuum pipe ?

With the noise you described that's what I would be inclined to say. What RPM does it loose pressure (do you mean boost? if so what does it go down to?)?

my second turbo i think ain't even came on because i tend to lose pressure at 0.65. so that would be cause by a vacuum pipe ?

yes mate possibly,

if the vacuums are connected wrong the second turbo wont come online properly, or like wise if the vacuums have a split.

the vacuums controll the turbo pressure, and time they come online etc.

yes mate possibly,

 

if the vacuums are connected wrong the second turbo wont come online properly, or like wise if the vacuums have a split.

 

the vacuums controll the turbo pressure, and time they come online etc.

But it could be a sticking VSV as this too would prevent the second turbo coming on line and could have caused the split vac line.

But it could be a sticking VSV as this too would prevent the second turbo coming on line and could have caused the split vac line.

Im going to have a check right now on the vacuum pipes. I only recently changed most if them but i check just to make sure

about when it lose boost, you hear it spool up then around 2500rpm ish the wired sounds comes on and at 3500rpm no sound.

Mine has just done this today, no unsual noises, 1st turbo kicks in, showing 0.68 on boost gauge, but no 2nd turbo.

If you have a stock/aftermarket blow off valve, check that. My stock one was alvays open so all boost was being lost back into the inlet after the filter.

bov is fine checked that. going to check all the vacuum lines tomorrow.

1st turbo boosts to 0.6 bar but 2nd turbo doesn't kick in at all.

Must be split pipe.

Sure its not Turbo spool? lol

But if you have a leak somewhere (boost pipe half off or something) the turbo spool will be really load, let alone the hiss from the boost escaping past the split or loose boost pipe

I recently had a similar issue.

Two of the vac pipes at the rear of the engine needed replacing. They were not split but had expanded over the years and although they were still on they were leaking!