OM654 anyone know what this part does?

[Manc Rick]

This part / cover fits to the front of the 654 engine and there are two pipes that connect this to the air intake, so air comes in through the intake then before it reaches the filter, these two pipes join onto the part (below) part no. a6540103102, taking some of the air to nowhere it would appear? Seems to be completely sealed and looks pointless (I’m sure it probably isn’t).

I noticed that the two pipes had disconnected on mine, so I pushed them back on but it got me wondering what the purpose of these two pipes are? Anyone know?

 

[Manc Rick]

Edit - I’ve answered my own question; it is an intake resonator! Learn something every day!

 

[mioba]

Ha ha. Thanks for update

 

[Manc Rick]

Just to give a bit of context, in case anybody encounters similar; I had been hearing a very peculiar noise particularly when first starting up in the morning, when accelerating in 1st/2nd, like a droning / resonance noise.

I discovered fairly quickly that the two (pictured above) pipes had become ‘disconnected’ from the air intake and after connecting them, the noise has not only gone, but the car is running better all round.

Such a simple part obviously has a very noticeable effect!

A bit of research tells me it is because the air flows up through the intake, past the air filter, into the engine, but when the valves are closed and that air has ‘nowhere to go’, it ‘bounces’ back down the intake, causing some kind of resonance. These two short pipes apparently counter / dampen that resonance and what a difference.

I (like most here) am very tuned to the behaviour of my car (some family members would say I have extreme OCD) - I’m not talking the sort of noise the Mrs would notice (if she was allowed to drive it), but definitely noticeable to my ears.