Turbo Siren

[GH421]

Hi,

This is unrelated to Mercedes however i'm completely stumped on this issue.

In addition the merc i have a 530d and i've recently fitted a new turbo to the car.

I've noticed that upon spool up the turbo sounds like a siren.

at about 2000rpm for half a second there's a siren sound and then suddenly the power rushes through and she flies.

I've looked at the pipes everywhere and can't find any leak

Any idea where to look?

The noise is coming from somewhere near the turbo but can't put my finger on it.

Fitted a new Exhaust Manifold gasket so that's covered.

Only thing it may be is the pipe which goes to the intercooler. It's made of steel but the seals are rubber and one looks a bit worn.

Could it be this?

 

[AndyPCD]

It could also have a crack in the intercooler i have seen this before.

The only other thing would be to remove the pipes and inspect them that way.

Where did you get the turbo from as i would speak to the company you got it from if its brand new

 

[GH421]

I did a swap + cash with Essex Turbo's.

To inspect the intercooler would that mean taking it out? To do that i would need to remove the whole front end of the car. eeeeeekk!

Any other test i can do to check it?

 

[AndyPCD]

I take it you cant here the noise if the car is just revved when stationary.

Is essex turbos a place that just supplys the turbos or do they fit them as well as if they fit the turbos it might be worth taking it down there for them to have a listen and quick look at

 

[matt17081]

just a thought and i've not tried this, but have you thought about spraying the pipes and intercooler with a soapy water solution and having a look to see if you can see any bubbles forming whilst the turbo is giving boost?

 

[EDZ649]

I used to own a 3.0 Dti Vauxhall Signum which made a similar noise. It was so loud I often thought an emergency vehicle was behind me! I never did get to the bottom of it!

 

[GH421]

the car makes the noise while stationary and revved up.

Essex Turbo only fix turbo's they don't do cars.

Good idea about the soapy water i will try that tonight! :bannana:

 

[GH421]

Checked the intercooler and it's fine. No leaks whatsoever.

One guy who's an expert on Jap Turbo's recons it's the gasket which sits on the turbo and the exhaust.

He also says he can hear to sets of noises, one at 2000rpm and one at 4000rpm.

What does a smoke test involve?

Has anyone used Middlesex Tuning?

 

[Lugy]

A smoke test is an MOT test where they will hold the engine at high revs (could be on the governor,I can't remember) for a short time.

I'd look into having the inlet pressure tested.

 

[AndyPCD]

As lugy says it could be the test they do on an mot.

I have not personally used middlesex tuning but dont think they are that bad the used to specialise on cosworths and rs turbos years ago not too sure what they do nowadays.

Are you thinking of taking the car to them for them to have a look at it