Idle high pitch rotation sound - Metal on metal squeal

[Honda]

Originally Posted by Route 16

I've had the same sound for 6k miles after I installed my iPE muffler

Cool, so at least I know it's the ICV and not a loose ITB clamp

The noise sound more like idler pulley. How would you know it is ICV and not thr pulley?

[Route 16]

Originally Posted by Honda

The noise sound more like idler pulley. How would you know it is ICV and not thr pulley?

my sound is coming from the back end of the plenum (drive side), idler pulley has normal sound

[Shamza]

Originally Posted by Honda

The noise sound more like idler pulley. How would you know it is ICV and not thr pulley?

Sure you shouldn't just go replacing parts if you don't know where the problem lies.

In my case, I ran the car without any belts first thinking it may be a bearing sound but sound was still present.

Purchased a stethoscope and pin pointed the sound from ICV.

Lastly you can disconnect the ICV and run the engine, have a friend hold the normal idle rpm. No high pitch squeal/whistle.

Also vacuum related problems can cause a similar sound, you really need to diagnose before replacing parts.

[Honda]

Originally Posted by Shamza

Sure you shouldn't just go replacing parts if you don't know where the problem lies.

In my case, I ran the car without any belts first thinking it may be a bearing sound but sound was still present.

Purchased a stethoscope and pin pointed the sound from ICV.

Lastly you can disconnect the ICV and run the engine, have a friend hold the normal idle rpm. No high pitch squeal/whistle.

Also vacuum related problems can cause a similar sound, you really need to diagnose before replacing parts.

That's exactly what I am trying to do. I want to pin point the problem but there are too many variables?
How safe is it to run engine without belts? I am also superchargered which adds other variables as well.

[strokemycocktus]

For example I had all the pulleys checked by the mechanic during rod bearings swap and all came out fine. He also was checking for the noise with a sthetoscope and it looked like the ICV area.
No codes on my car so far, but I know previous owner was troubleshooting idle problems caused by a wrong tune and he replaced the stock ICV (car is low mileage 2010) with a used one.
I also bought a used one very cheap, plan to clean it and see if it works then. Further diagnostic would be probably more complicated and costly than this easy swap
I will report in a few days hopefully

[Shamza]

Originally Posted by Honda

That's exactly what I am trying to do. I want to pin point the problem but there are too many variables?
How safe is it to run engine without belts? I am also superchargered which adds other variables as well.

I think you'll want to get a stethoscope as it will help you narrow it down. If it is from a pulley bearing you could take belts off and spin them independently, you'll be able to tell a good bearing from failing/failed ones from the resistance feel and sound.

It's fine to run engine without belts for a short time (<1min). Ensure the battery is decent and a cold engine as coolant won't be circulating.

[Shamza]

Originally Posted by strokemycocktus

For example I had all the pulleys checked by the mechanic during rod bearings swap and all came out fine. He also was checking for the noise with a sthetoscope and it looked like the ICV area.
No codes on my car so far, but I know previous owner was troubleshooting idle problems caused by a wrong tune and he replaced the stock ICV (car is low mileage 2010) with a used one.
I also bought a used one very cheap, plan to clean it and see if it works then. Further diagnostic would be probably more complicated and costly than this easy swap
I will report in a few days hopefully

Sounds good. Can't imagine any codes being thrown until it's completely died to be honest, but then your engine will stall so you'll already know something is wrong

[strokemycocktus]

I have just replaced my ICV. I have used the tutorials posted on the forum and BMW TIS, which was a bit more clear for me. Either way getting this out and back in was a big pain in the ass. I found all the metal clamps pretty hard to release and secure.
The unit I have removed looked better and newer than the one I was about to install. The housing was cleaner and the valve itself had less carbon buildup. The first two pictures show my original ICV, the second two the replacement one after cleaning.

Here is a video from yesterday (engine warmed up):

And here after I put everything back together after replacing the ICV:

As you can hear the sound is completely gone!
Given that my original ICV had almost none carbon buildup, my guess is that it is not the cause. I have taken the original unit apart to see if there was any damage - you can see for yourself in the last picture. All the gears were in perfect condition, moving freely, electronics looked fine, everything seemed to be in order. IMO this must be an internal failure of the motor driving the gears.

Shamza Big thanks again for pointing me to the right direction!

[Shamza]

Originally Posted by Shamza

I think you'll want to get a stethoscope as it will help you narrow it down. If it is from a pulley bearing you could take belts off and spin them independently, you'll be able to tell a good bearing from failing/failed ones from the resistance feel and sound.

It's fine to run engine without belts for a short time (<1min). Ensure the battery is decent and a cold engine as coolant won't be circulating.

Edit: Just saw your video in your other thread. I'd willing to suspect that's your water pump or potentially idler pulley. Get belts off and give all pulleys a spin.

[Shamza]

Originally Posted by strokemycocktus

I have just replaced my ICV. I have used the tutorials posted on the forum and BMW TIS, which was a bit more clear for me. Either way getting this out and back in was a big pain in the ass. I found all the metal clamps pretty hard to release and secure.
The unit I have removed looked better and newer than the one I was about to install. The housing was cleaner and the valve itself had less carbon buildup. The first two pictures show my original ICV, the second two the replacement one after cleaning.

Here is a video from yesterday (engine warmed up):

And here after I put everything back together after replacing the ICV:

As you can hear the sound is completely gone!
Given that my original ICV had almost none carbon buildup, my guess is that it is not the cause. I have taken the original unit apart to see if there was any damage - you can see for yourself in the last picture. All the gears were in perfect condition, moving freely, electronics looked fine, everything seemed to be in order. IMO this must be an internal failure of the motor driving the gears.

Shamza Big thanks again for pointing me to the right direction!

Glad you resolved it mate, the sound is probably white noise for most people but once it disappears it's bliss isn't it

Interesting how clean that butterfly is, perhaps someone already tried to clean it or it's been replaced before.