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Hopefully you guys can hear it clearly in the video but every time I startup my car, doesn’t matter the temp outside, there’s this high pitch whine that is there for a while and typically goes away once my car is at operating temp. I took off the top o2 sensor and removed the heat shield from the cat converter, didn’t see any cracks or anything there.

I’m convinced it’s an exhaust leak because I always smell an exhaust/oil smell when I drive my car from my vents, it comes and goes but it’s definitely noticeable.

Anyone have any ideas what it could be?

Video -


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Check the pulleys. Remove the serpentine belt and spin each pulley by hand. The tensioner pulley especially is known to go bad.
 

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Discussion Starter #3
Check the pulleys. Remove the serpentine belt and spin each pulley by hand. The tensioner pulley especially is known to go bad.
I actually discovered it was in fact an exhaust leak! Had a feeling it was. It was at the bottom of the cat converter, not sure of the exact words but the very bottom connection that connects to the rest of the exhaust system was leaking air there. I feel like just a gasket needs to be changed but the whole bottom of the cat looks really rusted, so I think I'll throw a new cat on with new hardware to freshen it all up. Explains why my exhaust sounded really rough, too.

Also, I changed my tensioner pulley a few months back so that's still relatively new, but this sound has been here for a while and it goes away once the car is at operating temps but I'm happy I finally pinpointed where it's at.
 

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I actually discovered it was in fact an exhaust leak! Had a feeling it was. It was at the bottom of the cat converter, not sure of the exact words but the very bottom connection that connects to the rest of the exhaust system was leaking air there. I feel like just a gasket needs to be changed but the whole bottom of the cat looks really rusted, so I think I'll throw a new cat on with new hardware to freshen it all up. Explains why my exhaust sounded really rough, too.

Also, I changed my tensioner pulley a few months back so that's still relatively new, but this sound has been here for a while and it goes away once the car is at operating temps but I'm happy I finally pinpointed where it's at.
The typical reasons associated with a whining sound on cold starts are usually the belt that has hardened over a period of time and once the engine heats up becomes soft and the sound stops. Low power steering fluid also gives out a whining sound.

Exhaust leaks don't exactly give out a whining sound. Small leaks give out the sound of leaking air and bigger leaks are characterised by louder and gruff exhaust note.

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Discussion Starter #5
The typical reasons associated with a whining sound on cold starts are usually the belt that has hardened over a period of time and once the engine heats up becomes soft and the sound stops. Low power steering fluid also gives out a whining sound.

Exhaust leaks don't exactly give out a whining sound. Small leaks give out the sound of leaking air and bigger leaks are characterised by louder and gruff exhaust note.

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Interesting, the serpentine belt was replaced last summer so that's still new-ish so it's not that.. I did check the power steering fluid reservoir and it is at the low level so maybe I should drain the old power steering fluid and put in new fluid to the top level and see if the noise is still there. I guess I just found an exhaust leak while looking for the cause of the noise lol I used the shop vac trick where I plugged my exhaust with the hose and pumped air into the system and sprayed soapy water around my cat and found a bunch of bubbles where there's a gasket I believe so it's probably leaking air there, I do smell exhaust through my air vents so it's most likely coming from that.
 

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Hi friend.
I had a whine on startup that would go away as the car warmed up. It sounded a little different than your sound, but its hard to tell with your motor running (my whine sound sounded like an electric motor whine when in the cabin). For me, this particularly happened in winter, but not always.

I discovered I wasn't putting enough transmission fluid in after a transmission fluid change (after a change, I would fill it to full, but apparently i need to drive the car around a bit and then fill it some more... i was always wondering why I was putting in a bit less fluid than what the manual indicates the car needed). So i think the pump whined a bit until the fluid or parts heated up.

If you change your transmission fluid yourself, this would be an easy check to see if the whine goes away.

good luck.
 

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Interesting, the serpentine belt was replaced last summer so that's still new-ish so it's not that.. I did check the power steering fluid reservoir and it is at the low level so maybe I should drain the old power steering fluid and put in new fluid to the top level and see if the noise is still there. I guess I just found an exhaust leak while looking for the cause of the noise lol I used the shop vac trick where I plugged my exhaust with the hose and pumped air into the system and sprayed soapy water around my cat and found a bunch of bubbles where there's a gasket I believe so it's probably leaking air there, I do smell exhaust through my air vents so it's most likely coming from that.
Lets hope that filling up the power steering fluid helps to solve your problem. And even though you replaced the serpentine belt only last summer, if the belt had been from an old stock that had been lying around for some time, it could've hardened over a period of time and still cause the sound, although this is a rare instance. So it is advisable to buy all rubber parts, including the tyres, from the most recent production batch.

If you had been smelling the exhaust fumes when the car is stationary, the leak you found out could be the cause. But if you are smelling while driving, then either the leak could be up front under the hood or the flap that opens or closes with the option of the recirculation air or outside air could be the problem where it isn't fully closing when the recirculation air option is selected and letting in the exhaust fumes in traffic. It also advisable to check the cabin air filter for any leaks.

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