Originally Posted by darrin (Post 12034224)

@thisisgoodnews -- did you replace the idle speed adjustment screw o-ring and/or investigate that as a source of noise?

Originally Posted by thisisgoodnews (Post 11992993)

Tried to do a quick search but with very little luck - so apparently a hissing / whistling sound developed when throttle is applied, occurs at low, around ~2k rpm. In the video, engine is at running temp, idle is stable, everything else is seemingly normal - no other strange sounds.

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Any hints where should I look first would be appreciated.

Originally Posted by thisisgoodnews (Post 12034133)

Anyhow, first think, I put back the stock cover, the sound was still there, but much less audible, and almost inaudible from the inside of the car, when driving. I am sure, If I also put the stock air filter in, the sound would be totally gone. I also serviced the air filter, washing and spraying it with oil, and the note of the sound slightly changed. So my theory is, as I didn't oil the filter when taking it out the box when installing it (it was oiled from the factory), the oil might have dried out in some time, and the sound became more and more obvious. So this case is closed.

Originally Posted by pmax (Post 12034372)

Some "knocking" sounds at 0.07 and 0.17 or thereabouts ... hear them ?

Originally Posted by pmax (Post 12034372)

Perhaps, the filter loosened up after a while and the reinstallation fixed that. The OEM clips hold the lid down tight, compressing the air filter frame evenly all around in the process.