A mechanic just went viral for sharing a video of a Chevrolet making owl-like noises. 

Zach Dennis (@zach2.2) recently posted a video, which has amassed more than 20,000 views as of Friday, of unusual noises coming from a Chevrolet. “Customer states, under acceleration, my car sounds like an owl,” he says. “It’s a new one for me.”

Overwhelmingly, the comments pointed toward a consensus regarding the cause of the issue. “The PCV valve has failed,” wrote one comment. So… what’s going on here?

Could An Issue With A PCV Valve Cause Owl-like Noises?

The PCV (Positive Crankcase Ventilation) could very well cause the car to make a similar noise, though it is certainly not the only possibility. 

The PCV valve is part of the engine’s ventilation system. Its job is to route blow-by gases, a mix of unburned fuel vapors, moisture, and oil mist from the crankcase, back into the intake to be burned again rather than released into the atmosphere. This helps reduce emissions and prevent pressure build-up inside the engine.

When the PCV system starts to fail, symptoms can include oil leaks, rough idle, unusual emissions, and changes in engine performance, precisely because the valve affects vacuum and airflow into the intake manifold. 

A PCV valve issue more commonly produces hissing, whistling, or sucking sounds from vacuum leaks, essentially air being drawn in or escaping where it shouldn’t. That happens because the valve, hose, or diaphragm has deteriorated, letting unmetered air into the intake or making unusual airflow noises under vacuum. But these sounds tend to be sharp or hissy, so the sounds heard in the video are certainly an outlier. 

Reddit threads about GM cars with PCV or intake vacuum leaks often describe vacuum leaks leading to whistling sounds and rough engine performance, and sometimes they point out that the PCV system on some Chevy engines is integrated into the valve cover and not a standalone valve, complicating diagnosis. 

How Costly are PCV Valve Repairs?

Fixing a PCV valve issue is usually one of the more affordable engine repairs, though costs can vary depending on the car model and labor rates. For most Chevrolet models, a standalone PCV valve replacement typically runs between $50 and $150, including parts and labor. 

If the valve is integrated into the valve cover, like on some newer Chevy engines, the repair can be more involved, potentially reaching $200 to $400 as the mechanic may need to remove the cover, replace gaskets, and reassemble the engine components.

MotorBiscuit reached out for comment to Dennis via TikTok Direct Message and Chevrolet via email. 

@zach2.2 customer states my car sounds like an owl this is a new one for me #getwrenched #automotive ♬ original sound – Zach Dennis