[Herakles]

I just got my car back from shop they found the coolant leak was a cracked radiator. The same
Shop replaced it 1.5 years ago (Baer) and was under warranty, but still had to pay labor.
The lack of heat was so fixed they flushed coil but said little debris came out and was most likely due to air pocket bc of cracked radiator

When I got it back the car now makes a whistling noise when running, I do have a leaking valve cover gasket too, has to go back for so not sure if this is the pcv valve going?

[TheGoodTheBadTheUgly]

Wow, that is extremely high pitched. You can test the PCV valve by removing a covering nipple on it and holding tissue or a flame from a lighter next to that hole. If there is a vacuum and the tissue/flame is being pulled in the hole, you have a bad PCV. You can also open the oil fill cap when the engine is on and if the sound of the engine changes or there is suction while trying to lift the cap it would also indicate bad PCV.

I don`t think PCV valves cause such a high pitch noise, but worth a try!

[TunafishE93]

I would go with pulley/tensioner probably got fluid in bearings from coolant. If the issue doesn't resolve when taking off oil cap, you can pull belt and run to verify pulleys.

[Bmmrr]

I had a high pitch whistle just like that when I did an ofhg replacement.

turns out that I managed to disconnect a tube that, I believe, ran to the back of the car for the exhaust valve.

mine had disconnected at the front of the shock mount.

you can identify the pipe and follow it to check, you will be able to find it easily by looking by the hood hinge on the right and it runs down along the side, in from to the shock mount, at this point there is a short piece of rubber tube connected at both ends, and around under the airbox..

the whistle was just the engine vacuum sucking air in through the small pipe.

[Herakles]

Originally Posted by Bmmrr

I had a high pitch whistle just like that when I did an ofhg replacement.

turns out that I managed to disconnect a tube that, I believe, ran to the back of the car for the exhaust valve.

mine had disconnected at the front of the shock mount.

you can identify the pipe and follow it to check, you will be able to find it easily by looking by the hood hinge on the right and it runs down along the side, in from to the shock mount, at this point there is a short piece of rubber tube connected at both ends, and around under the airbox..

the whistle was just the engine vacuum sucking air in through the small pipe.

Thanks if you can snap a pic of what your talking about that would be great and what's a ofhg? The shop I had it for the working may of left it off. When I brought car home it had no power too think they had a charge or inlet loose and had boost leak. I brought it back they said they checked connections and didn't find anything but was fixed - not sure if they accidentally fixed it and didn't realize or didn't want to admit they had a pipe not couples right

[Herakles]

Can see here ?

[Herakles]

Originally Posted by Bmmrr

I had a high pitch whistle just like that when I did an ofhg replacement.

turns out that I managed to disconnect a tube that, I believe, ran to the back of the car for the exhaust valve.

mine had disconnected at the front of the shock mount.

you can identify the pipe and follow it to check, you will be able to find it easily by looking by the hood hinge on the right and it runs down along the side, in from to the shock mount, at this point there is a short piece of rubber tube connected at both ends, and around under the airbox..

the whistle was just the engine vacuum sucking air in through the small pipe.

You the man! After shoveling out the snow I thought let me check .. and I found it! When I connected it seemed to collapse the tubing is that normal,? What is it ?

[Bmmrr]

Originally Posted by Herakles

You the man! After shoveling out the snow I thought let me check .. and I found it! When I connected it seemed to collapse the tubing is that normal,? What is it ?

Hi

Sorry for not getting back sooner, I've not had any notifications.

So, it was that pipe than? glad I could help.

As I say, I'm not sure what it was, but like yours mine collapsed when I reconnected it and the whistle stopped.
I tried to follow it but without stripping some parts off I could not get to either end so just left it and assumed it was the vacuum pipe that ran to the exhaust flap.
When I reconnected mine it was quite loose so I put a small cable tie in each end to ensure it wouldn't come apart again.

The OFHG, is the oil filter housing gasket

[Herakles]

Originally Posted by Bmmrr

Hi

Sorry for not getting back sooner, I've not had any notifications.

So, it was that pipe than? glad I could help.

As I say, I'm not sure what it was, but like yours mine collapsed when I reconnected it and the whistle stopped.
I tried to follow it but without stripping some parts off I could not get to either end so just left it and assumed it was the vacuum pipe that ran to the exhaust flap.
When I reconnected mine it was quite loose so I put a small cable tie in each end to ensure it wouldn't come apart again.

The OFHG, is the oil filter housing gasket

Originally Posted by Bmmrr

Hi

Sorry for not getting back sooner, I've not had any notifications.

So, it was that pipe than? glad I could help.

As I say, I'm not sure what it was, but like yours mine collapsed when I reconnected it and the whistle stopped.
I tried to follow it but without stripping some parts off I could not get to either end so just left it and assumed it was the vacuum pipe that ran to the exhaust flap.
When I reconnected mine it was quite loose so I put a small cable tie in each end to ensure it wouldn't come apart again.

The OFHG, is the oil filter housing gasket

Yes! You were right on the money! When I plugged it back it made the hose collapse because it the vacuum I thought that was weird but the sound stopped just as you said thank you so much

[Welcome to NBA Jam]

That entire tube is for the exhaust flap. It can fall off very easily and leak a little oil. I zip tied the two ends of the rubber hose and tied the line a little more out of the way than the factory has it.

[SWalters]

Geez...why could I not find this thread a couple of weeks ago.

I've already replaced the PCV, and was about to order a valve cover or a smoke tester. Finally dug deep enough to find it tonight and came in to post in all the "replaced the PCV and it still whistles" threads that I've run across while looking for answers.

Who the HELL makes a vacuum line out of that crap? Did they just want the damn thing to be -expertly- camouflaged with all the corrugated wire covers??

[wheela]

I gotta check this on my car. No whistling, but i'm not happy with the big gap between target and actual boost.

[Herakles]

Originally Posted by SWalters

Geez...why could I not find this thread a couple of weeks ago.

I've already replaced the PCV, and was about to order a valve cover or a smoke tester. Finally dug deep enough to find it tonight and came in to post in all the "replaced the PCV and it still whistles" threads that I've run across while looking for answers.

Who the HELL makes a vacuum line out of that crap? Did they just want the damn thing to be -expertly- camouflaged with all the corrugated wire covers??

I know! It's insane you can just decouple it so easily !

[postaudi]

Just found the same issue on my car after doing some work on it, thanks for the easy fix!

Originally Posted by Bmmrr

I had a high pitch whistle just like that when I did an ofhg replacement.

turns out that I managed to disconnect a tube that, I believe, ran to the back of the car for the exhaust valve.

mine had disconnected at the front of the shock mount.

you can identify the pipe and follow it to check, you will be able to find it easily by looking by the hood hinge on the right and it runs down along the side, in from to the shock mount, at this point there is a short piece of rubber tube connected at both ends, and around under the airbox..

the whistle was just the engine vacuum sucking air in through the small pipe.

[greybmw335]

Originally Posted by Bmmrr

Hi

Sorry for not getting back sooner, I've not had any notifications.

So, it was that pipe than? glad I could help.

As I say, I'm not sure what it was, but like yours mine collapsed when I reconnected it and the whistle stopped.
I tried to follow it but without stripping some parts off I could not get to either end so just left it and assumed it was the vacuum pipe that ran to the exhaust flap.
When I reconnected mine it was quite loose so I put a small cable tie in each end to ensure it wouldn't come apart again.

The OFHG, is the oil filter housing gasket

By any chance do you know if this is the same way on the n54s? I just did a oil and filter change on mine and ever since than I’ve had a high pitched whistle just like the people in this thread.

Here is what mine sounds like:

https://youtube.com/shorts/ipNRrB2UvHY?feature=shared

[Canuck335]

I know it’s an old thread but just wanted to thank Herakles and Bmmrr for their posts. I had exactly this problem after changing a burned out DRL bulb and I must’ve disconnected the vacuum line in the process.