Whistle

[Howard]

Ok gang ,

I have a whistle .... its been bugging me for a while now , i'll give you the symptoms.

The engine only does it under load ( ie driving ) , it doesn't do it when you just rev it while stationary.

If you accellerate , it can be heard clearly , it begins at about 1500 rpm , when you let off and let the car coast , it stops ....

I have lubed all pulleys , belts and what not , it is definately not that.

It isn't a stone stuck in a pad .

The general concensus is that it may be a pipe drawing air , but to be honest i have absolutely no idea where to start looking as it won't do it when the car is stationary ....

Any ideas ? It really is spoiling the enjoyment of driving the car ....

 

[Dieselman]

If it's when under load it can only be something either pressurising or having high air-flow due to WOT.
This means it must be either the exhaust or intake tubing. I suppose it could be the crankcase vent valve.

 

[Howard]

In english please ....

 

[gina2201]

When I read the first line I though you meant YOU had a whistle not your car (oops)

 

[Dieselman]

It could be a blocked exhaust or leaky joint so only shows under power, also the intake is only under full suction when the throttle is wide open (WOT), so will reveal a leak or split pipe then.

 

[partsspecialist]

Depending on car/engine the intercooler pipe is always a favorite.

 

[BlackC55]

Does it sound like a beetle?

 

[Dieselman]

When I read the first line I though you meant YOU had a whistle not your car (oops)

Only when he builds up enough internal pressure...

 

[Dieselman]

Depending on car/engine the intercooler pipe is always a favorite.

But not on a 320..

 

[Dieselman]

I also wonder about the resonance flaps being jammed in the high torque position causing restriction when under fiull throttle.

 

[Howard]

It isn't when it is under full throttle , weirdly , when it is under full throttle the noise is gone .

Olly , i know i was saying it sounded like a beetle at the GTG , but now it sounds kinda different ...

Doesn't sound like i am going to be able to sort this myself does it ?

Sorry should have said , its on a 99 320 CLK .

 

[grober]

Leak in the line going to the evaporative control charcoal filter under the wing?

 

[KillerHERTZ]

It isn't when it is under full throttle , weirdly , when it is under full throttle the noise is gone .

Olly , i know i was saying it sounded like a beetle at the GTG , but now it sounds kinda different ...

Get your Mrs to hang out of the window recording the a video of the sound while you drive it

Will be a help knowning exactly what the sound, sound likes

 

[jaymanek]

we should have gone for a drive at the GTG as im pretty sure this is the normal squeely noise that a lot of the 320 engines make...

 

[Vlad]

Could it be from the gearbox when its under load?

 

[Howard]

It sounds a little bit like when you whistle through your teeth ...

 

[jaymanek]

It sounds a little bit like when you whistle through your teeth ...

thats normal!!!

I could show you lots of 320's here with that noise...

Its something to do with the harmonic balancer but MB always just said it was a characteristic of the engine...

 

[Howard]

I honestly have not heard another car make a noise like this ...

I might have a trip to Ollys when i get a spare weekend , see if he could have a look at it for me .