Astraelraen

New to me Porsche seems to be making this squealing sound, you can hear it inside at idle / when stopped. Haven't really tested on cold starts, but has happened at operating temperatures multiple times. It made it 650 miles presumably making this noise the entire way so it must not mean eminent failure.

Any ideas? Concerns? Who cares just drive it?

Video is with my smartphone holding it over the closed engine cover.

Dripola

Petza914

Can you remove your oil fill cap with the engine running or is it being sucked down by vacuum where it's impossible to get off - that's an AOS test. If not that, remove your airbox and serpentine belt and spin and try to wobble each one if the pulleys by hand until you find the one that has play in it or doesn't rotate freely.

Astraelraen

Sorry its 2010 997.2 S

Was going to call mechanic Monday and schedule a spark plug, etc change anyway. I will test the oil cap this morning and fiddle with the airbox, I saw a howto for the 997.2.

Thanks for the pointers, I appreciate it.

Astraelraen

On cold starts there is no squeal. Tried to take oil cap off and it comes off fine-ish?

If I let it sit and idle for 5 minutes or so I still don't get any squeal but taking the oil cap off seems to make it drop idle and run roughly. Also sounds like an air leak you can definitely hear air/vacuum/something.

I will likely ask dealer to take a look at it anyway.

Petza914

Just to confirm, you tried to remove it with the engine running, correct? If so, I don't think warm or cold should make much difference.

Astraelraen

I didn't drive it today, I let it sit in the garage and idle for about 5 minutes. Since I've never taken an oil cap off a 911 I can't say if it was "difficult" to remove. I might have described it as feeling as if it was being sucked back on.

But​​​​But yes, I removed the cap while the engine was running and the revs dropped and it started running roughly until I put the oil cap back on

Petza914

You'd know if it was difficult. It would be almost impossible to remove it if you had an AOS issue. This means its probably a noisy pulley or bearing on the serpentine belt system. One other test would be to press the Eco button on the HVAC panel which will turn off the A/C compressor to eliminate another possible source (A/C compressor clutch or bearing).

Astraelraen

Thank you for the help! The morning temps are below 40 for most of this week so the 911 probably won't get driven much due to my work schedule. I will report back when I get any updates.

Maan

Astraelraen

This noise has actually gone away completely - as in I can't hear it anymore, which I find unusual. I've put about 800 miles on it since intially hearing the noise.

I am getting some catch up service work done, including check/change the belt in early November. I will probably have them check all the pulleys/tensioners while its there.

Astraelraen

I had the dealer do some service (spark plugs, replace serpentine belt, various other items) and they said they checked the pulleys for play while replacing the serpentine belt. I asked the service advisor and she said that none needed replaced.

I drove it this morning, the squeal is still there some days same as above video, I can hear it at idle/stoplights, some days cant hear it at all.

It's going to sit for a few months soon as the temperatures will dip too low to drive it here.

Iceter

bgoetz

mbatarga

Sounds like a bearing issue to me - tensioner pulley - or water pump perhaps?