M54 intake noise, sounds like it's got bronchitis!

What could this be?

It seems to be common, or perhaps even normal ? There's plenty of videos showing it on youtube.

I have replaced both intake hoses (hose from MAF, and lower elbow to TB).

The DISA is OK, and I also RTV'd it since the O-ring looks dead.

But basically it sounds like a person who's nearly dying in hospital after smoking 60 a day all their life.

Is it the design of the ICV ?

My last straight-six was a 2JZ-GTE in Supra, and you could barely tell it was running at idle.

The noise is quite similar to that of a worn out tensioner pulley, if that helps.

You can hear it here.
In his Youtube video description the guy says "see, it's nice and quiet now" (after he fixed his broken DISA).
Well, not only does it still sound clattery to me, but listen to that intake noise at 7 seconds into the video. That's what I'm talking about.

Go back to supras

Sent from my SGH-T959V using Bimmer

Originally Posted by darksideracer69

Go back to supras

Sent from my SGH-T959V using Bimmer

That's not terribly helpful, but thanks anyway!

It seems like that video is during initial start up. It that case its normal.

Sent from my SGH-T959V using Bimmer

Hmm. I haven't waited to see if it stops after a while. I will see.

Having had the ICV out today and cleaning it, I am wondering if it's simply a side effect of the design of the ICV - the way it restricts/controls airflow. I'm not sure how other ICVs work, but I know the Denso type don't look or fit onto the manifold like this. If I remember rightly the Denso one is a plunger that goes into a specially constructed crevice on the intake manifold/plenum, whereas this type is just a straightforward restrictor valve plumbed into a hole in the side of the manifold.

The noise isn't noticeable when driving. I just want to be sure that everything is as it should be. I haven't had the car long and have had to replace quite a few things on it right away.

I just monitored a 10 minute drive via OBD.

Short term fuel trims are running between 22 and 27%. Occasionally going closer to 0, but most of the time around those high figures. I think I must still have a vac leak, and that may be the source of the noise.

I've ordered a replacement o-ring for the DISA unit, and will get a new throttle body gasket too.

I got a "System too lean (bank 1 &2)" earlier today.