General Whistle at accereleration

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General Whistle at accereleration

Joined
Jun 6, 2008
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Location
ireland
Hi to all,

I was looking at a 2006 1.3 multijet wheelchair vehicle yesterday with the intention

of buying it. I noticed that while i accelerated it up through the gears, it has this what

I can only describe as a Whistle sound. It sounds as though its coming from the engine.

It was suggested to me that its a Turbo Whistle.

Would this be anything I should worry about? Is it safe to buy or not?


Thanks for looking.

John.
 
Was it very predictable.. or came and went?

Not necessarily a major fault..
But could be louder than 'normal'.etc

I have that engine in 2 GPs

THE LOUD ONE.. isnt as refined..or as good on fuel ( I suspect an induction leak)

Drive another for a comparison :)
 
Likely to be an air leak in the intake somewhere. I'm not sure of the layout of components, and cannot be bothered to peer at Haynes, so here are general principles.

If it is sucking, before the airflow meter, it is mostly an annoyance, as it is unlikely to draw in harmful stuff that should be caught in the air filter.

If it is sucking after the airflow meter, you are pushing more air in than the fuel is using. Less power than you were hoping for. Running weak is not a problem for the diesel.

If blowing air out, this will be after the turbo. If before any airflow meter, the meter will still measure what is going into the engine. Again, more of an anooyance, but still needs to be fixed.

If blowing air out after the airflow meter, you will be getting less air into the engine than measured, leading to overfuelling. Lots of soot/black smoke, poor fuel consumption, and if it has a DPF (diesel particulate filter) that will clog very quickly, requiring frequent regenerations, using lots more fuel.

Air leaks can be located using soapy water on the pressure side, it blows bubbles, or something like WD-40 on the intake, it gets sucked in and changes the engine revs.

If it is the turbo whining, this is a symptom of lack of lubrication, or lots of wear. If so, find another vehicle as a new turbo is expensive.

That's all I can think of immediately. Others may be able to add.
 
Was it very predictable.. or came and went?

Not necessarily a major fault..
But could be louder than 'normal'.etc

I have that engine in 2 GPs

THE LOUD ONE.. isnt as refined..or as good on fuel ( I suspect an induction leak)

Drive another for a comparison :)



Here's the latest varesecrazy,

I bought the Doblo. The owner said the whistle has been the vehicle since he

bought 3 years ago, and never gave an ounce of trouble. After taking the Doblo for

good stiff drive the turbo kicked in very quickly.....very responsive. He suspects a

turbo high pressure side of the inlet manifold, which sounds plausible enough. As

far as he is concerned, its never been an issue. He maybe right, but me being me,

I have to get to the bottom of the issue, and correct it.

I drove it home, a trip of 150 miles and didn't skip a beat very pleased.

Tipping along the motorway at 65 miles per hour....no whistle, it only happens when

you apply the accelerator. Going downhill no whisle, as soon as you press the gas


pedal then it starts. The more you press the louder it becomes. it might be a leak.

Thanks for your suggestions.


John.
 
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Hi portland bill,

As you have also suggested it looks like an air leak. I'm ruling out the turbo whining

because I only get the whistle under acceleration, if I'm correct the turbo would

sound all the time due to wear. This is not happening here. But I will remove the


the air intake hose and check for movement on the shaft. Take nothing for granted,

check everything. I'd also rule out blowing air out after the airflow meter, because

no smoke of any kind, with excellent power and good fuel return. But I'll check

this area as well to be on the safe side.

I made my own smoke machine a little while back, and works a treat. So I'll use

this machine at various locations on the inlet system.

From the suggestions that have been made, an air leak looks like the most likely.

Thanks a mill for your reply. Most appreciated.

John.
 
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