Noise when letting off the throttle
 

When I am in neutral and give it a little bit of gas then let off I hear a weird noise almost like a pressure release/hiss, is this normal or does anyone have some insight on what this could be? When I rev it up past 2 or 3k rpm it seems to go away a bit. When it was cold I first heard it and blamed it on the weather but last night I tried it again and got the same noise just not as dramatic.

I'll try and post a video of the noise later on.

Any insight will help, thanks in advance.


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Do you have HFC's, test pipes, or long tube headers? If so, this is normal.

I have HFC's, it's really noticeable like from 3500 rpm down to 2500 rpm. Just normal for our engines OP. No worries!

No everything is stock, you guys feel it is normal still?

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You have a loose OEM exhaust head shield - fixing it will be a PITA because the bolts are near impossible to get to

Thanks for the response, I tried to research and it looks like heat shield is sitting after the cats (If I'm seeing things right), the noise I have comes from the engine bay. Do you think the heat shield could cause a sound from the sound from the engine bay?

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I looked at the diagram for the heat shield again, I actually don't know it's exact location. Any help would be aporeciated.

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The heat shields are clamped onto the OEM headers upstream of the cats.

They are a B1tch to get to.

You need the car on a hoist and be looking underneath to get at the clamps that fix them to the OEM exhaust manifold

https://youtu.be/CncQEYeQt3A

I was finally able to get a short clip of video, you can hear the hiss/gasp noise after I let off the throttle. Still think it is the heat shield??

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That's a natural sound for this engine. If you put hfc/test pipes, it'll be louder

Doesn't sound like anything to worry about there.

Thank you guys, I just wanted to make sure it was a normal noise for this engine. Your help is much appreciated and calms my nerves a bit. Haha

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