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Unknown noise - please help

I have this noise in my car almost all the time the engine is on (idling or not). I can hear it more in the night when it’s more quiet

Appreciate if you can tell me what is that? Is it urgent to get it repaired?
I have this noise for almost 1 year
It’s Pontiac Wave 2007 (like Chevrolet Aveo) with 92,000 km

My lame home computer won’t run videos :see_no_evil: or audios :hear_no_evil:. I wonder if anybody who’s run them can describe the noise a bit.

Is it an external sounding noise, like pulleys/belts/heat shields?
Is it an internal sounding engine noise?
Can’t tell?

One should always be sure the engine oil is fresh, the proper specification, and up to proper level. If the noise started after an oil change and an aftermarket filter was installed, I’d suspect it as a culprit and install an Original Equipment filter.
CSA

Where were you holding the microphone when you recorded this?

I assume you’re talking about the tapping sound?

For those without a video player, it sounds like rain on a metal roof.

I was placing the mic outside of the car just in front of the hood. The hood was closed.
Yes it’s like rain on metal roof but very fast rain

Time to open the hood and have a look, could be a drive belt coming apart a failing water pump or an internal engine noise.

Maybe the valve tappers are out of adjustment. The 1.6L engine uses bucket tappets.

I think noise is coming from engine compartment? Open the hood and look around? Why are you recording sound from engine area with hood closed?

I have no ideas from the audio but it is very loud. Raining golf balls on a metal roof?

I’d guess that it is an exhaust noise. Somewhere the exhaust is vibrating against something.

Yosemite

Or perhaps there’s a leak. I’ve heard an exhaust leak sound like out of adjustment valves.

Greg, Greg, Could you take a look, take a look, at that paragraph I submitted earlier and comment on it, please, please. Thanks, thanks.
CSA, CSA

Thanks a lot for your comments. I indeed opened the hood but couldn’t see anything abnormal.
I changed the oil twice so it’s not after changing oil , but maybe the oil filter since it was not replaced recently with the oil change.
Can it be the timing belt noise or water pump noise??
I hope it’s exhaust vibration.
I’ll try to do more investigation.
Please let me know if you have more comments.

Replace the filter every time you change oil. It is called an inexpensive way to avoid an expensive problem.

With the hood up, start the car cold, then CAREFULLY feel around the front (belt end) of the motor and see if you feel a rapping through the metal corresponding with the noise (which is pretty awful, by the way).

I wholeheartedly support that philosophy. To do otherwise is penny-wise and pound-foolish.

Good call. I’m an experienced exhaust specialist. I have just never heard an exhaust rattle that severe. Broken motor mount?

I’ve heard that sort of “rain on a metal roof” sound one time on my truck. It was a pretty severe case of engine pinging. I had just completed a repair and reversed a couple of vacuum hoses by mistake, and full vacuum was going to the advance control on the distributor. So I was getting something like 25 degrees advance at idle when the base timing should be around 6 BTDC. It made quite a racket, I must say. If anything that might have changed the ignition timing was done recently, consider pinging as a possible cause.

I can’t listen to the sound, but it could be carbon build-up in the combustion chambers. There’s a general TSB about it for these vehicles.

It would be interesting to know how this low-mileage vehicle was operated and if it ran on TOP TIER gasoline.
CSA