What's making this whistling sound??

[Ontario Sonic]

Hey all, i took a look around the forum and couldn't find a thread that covered this issue, at least not all the parameters of it so i created a new thread and i hope you can help me figure this out.

I've had my Sonic for about 6-7 weeks now, and as far as i know this sound wasn't there when i bought it. I noticed a couple days ago when i pulled into the drive way, i got out of the car before i turned it off and i noticed a slight high-pitch whistling sound. Now, when i am in the car i can not hear it at all, driving and everything all sound normal and the car is running perfectly fine with no issues. The sound only seems to appear when i am parked and every time i have heard it, all HVAC systems were off and the car was at idle.

I am not losing any coolant and the water pump seems fine (others on the interweb seemed to point to coolant loss as a potential culprit) and it does not seem to be coming from any of the pulleys in the serpentine area. Another discussion i read for someone having a somewhat similar issue to me one of the respondents said that it might be the turbo wastegate letting off pressure or something to that effect, and that it was normal, so i'm not sure. All of my previous automotive experience has been with 3800 series II engines as all my previous cars have had them. So little 4 banger turbos are a brand new experience for me and i'm not sure what all is normal yet.

I've included a video i took this morning of the sound, and it seems like it might be coming from one of the lines in the back left of the engine bay, up against the firewall, although i may be mistaken as sound likes to trick you in tight spaces like that.

If you want to watch the video and give a listen, maybe one of you guys can help and tell me if this is normal or abnormal.

It is important to note that the mic on my phone really picked up the sound and kind of blew it out of proportion, the actual whistling sound is probably 25%-35% quieter than it sounds on the video, if that helps with diagnostics. Thanks in advance for any help

https://www.youtube.com/watch?v=faUsRo-hncE

 

[Luv2xlr8]

That would bother me also, it sounds like my honda that has a 3 inch short ram intake but yours is louder. That's quite annoying if I had to drive that, hope you figure it out.

 

[Ontario Sonic]

It really isn't that bad, like i said my phone's mic really picked up on the sound, standing there with the hood open it is 25%-35% quieter, not really too loud, with the hood closed it is closer to 65%-75% quieter and once you get in the car you can't hear it at all. Also, when i am driving, i can't hear anything. even with the radio off, HVAC off and windows down (or up) it all sounds normal. Just makes this sound at idle, from what i can tell.

Edit: After watching that video again on my computer rather than my phone, i would like to revise my earlier notes and say that the whistling sound is closer to 40%-50% quieter than it actually sounds in the video, rather than the 25%-35% figure i gave before. (my mic must be really sensitive to the higher range, it most definitely is not as loud as the video makes it sound)

 

[ohio_grad_06]

When I was having issues with my old dodge stratus I think I remember reading this could happen due to a cracked exhaust manifold. Might take a look at it and see.

 

[Maddmatts]

Maybe the valve cover's rupture disc ruptured?

 

[LTturboguy]

Had this same problem before its your water pump. Take it to the dealership and have them look up the TB for it, it should be a fix under warranty. I'll see if I have the paperwork for the TB somewhere, I had
Mine done at 3k miles...


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[Ontario Sonic]

Had this same problem before its your water pump. Take it to the dealership and have them look up the TB for it, it should be a fix under warranty. I'll see if I have the paperwork for the TB somewhere, I had
Mine done at 3k miles...


Cool, over the last few days of observation i have discovered that it only makes the sound when in park, after the car has been driving for a while and is warmed up. Not when it is cold or has warmed up, but not been driven anywhere. The sound is also intermittent, as i have noticed that even under the conditions i described, it still doesn't happen all the time.

Upon closer listening, it does appear that the sound is coming from somewhere in the serpentine area (suggesting water pump could be the culprit).

Also, a fellow commented on the video on YouTube that between the 24-30 second mark in the video, he said it looks as though my Intake Manifold may be beginning to separate. Can anybody confirm if that is the case (it's hard for me to tell and i'm unfamiliar with any issue like this) and if so, what that means for the car? I have the powertrain warranty for the next 2 years, and i think both of these potential issues fall under it, but i'd like to have a comprehensive list to give them and what to look for before i go in

 

[LTturboguy]

There's a thread on here called
Attn:if you're tuned, it's literarily about the intake manifold and its crappy plastic construction, if you have a tune the plastic pieces begin to separate due to the raised boost. It can cause rough idling/surging/loss of power. There a pictures in the thread for you to take a look at, that way you can definately tell if it is separating.


Here is the thread.

http://www.sonicownersforum.com/forum/showthread.php?t=19072

 

[Ontario Sonic]

There's a thread on here called
Attn:if you're tuned, it's literarily about the intake manifold and its crappy plastic construction, if you have a tune the plastic pieces begin to separate due to the raised boost. It can cause rough idling/surging/loss of power. There a pictures in the thread for you to take a look at, that way you can definately tell if it is separating.


Here is the thread.

ATTN: If you have a tune please read - Chevy Sonic Owners Forum

Awesome! Thanks I actually am running completely stock, with no plans to mod at all in the near future (probably next spring at the earliest) but i'll read through there anyway just for the info.

Moving back to the sound for a moment though. If the Water Pump is causing the sound, and given the information i gave in my last post about the sounds occurrence, the fact that it's reasonably quiet and intermittent, and considering that it doesn't appear that any coolant is leaking anywhere and the reservoir is still full, do you think the car would be safe for a roadtrip in the next couple days? I have a wedding to attend on Friday and it is a 350km journey 1-way (so 700km round) and i'd hate to experience severe car trouble stranding me far from home. So i guess my question is, is the sound just a sound and i can neglect it for another week or so, or is it something i should have looked at right away?

 

[LTturboguy]

I wouldn't think so but don't quote me on it.


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[Ontario Sonic]

I wouldn't think so but don't quote me on it.


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I am going to assume that "I wouldn't think so" refers to not needing to address it right away and not to not being able to let it slide for a bit, lol

Either way, i wouldn't quote ya on it, i'm just brand new to this car and these engines and architecture so i'm still in learning mode trying to gather as much info as possible so i can become an informed owner. All my previous cars have been 3800 Series II cars and i've become basically an expert on them to the expense of any other cars, so i'm a little out of my element here... :/

 

[LTturboguy]

You can probably get away with doing the road trip, I put like 200 miles on mine between when I finally investigated the noise and when the dealership finally had an opening to look at my car.

I probably had that noise for another 300 miles before that, I only heard it because I parked in a parking garage and I heard the echo.


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[Natesriv]

yeah it sounds bearing related (a.k.a. waterpump)

 

[Ontario Sonic]

You can probably get away with doing the road trip, I put like 200 miles on mine between when I finally investigated the noise and when the dealership finally had an opening to look at my car.

I probably had that noise for another 300 miles before that, I only heard it because I parked in a parking garage and I heard the echo.


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Awesome, thanks for all the help i really do appreciate it. I have been listening for the sound and haven't heard it in 2 days until tonight, so it is definitely intermittent and likely really early in the process so i'll let it slide for a bit until i have a little free time to take care of it. It helps not having to panic that the engine is gonna fall apart or something on the journey (not that i'm an alarmist, but as a car guy, when somethings ailing with your 2nd love, your mind starts wandering to worst case scenarios ) Once i do get it looked at/taken care of, i will repost here just to let you know if it was indeed the water pump or if it ends up being something else.

 

[LTturboguy]

Oh trust me the manifold separation anxiety has me on edge in that past few days, I know the feeling.


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