Help me get to the bottom of my weird header noise

[bmorecam]

Originally Posted by kencam

You could try disconnecting your fans. Tie a strip of tissue paper on a stick and go hunting!

That sound doable LOL I might have to try that but I think the first thing I'm going to do is go through all the welds. Most of the noise seem to be coming from the passenger side. That side might be the culprit.

[BLACK10]

Originally Posted by bmorecam

That is one place I didn't check. I'm going to check that area first thing tomorrow. There's definitely no leaks around the top though. I been dealing with this noise for almost a year and I'm sure if there was a year worth of leak there should be some black soot but nothing.

Also, I just want to clarify that is not a rattle like a heat shield loose but it's more of a hiss mixed with a hand shaker instrument like in the pic. It's weird even trying to explain the noise LOL.

Im really saying that you might not see it from the outside. I think it may be a broken weld on the inside.

Like in the area like this picture, or a broken cat if you installed them at the same time

[bmorecam]

Thanks black 10. Never thought of the welds on the inside. It definitely could be.

[GEEo]

I have that raspy sound on mine also I thought its just exhaust gas passing through the manifold.

When I had the stock manifolds on that sound wus also there but it wasnt as noticable when I got mt LT's installed.

I always thought it wus normal.

[bmorecam]

Originally Posted by GEEo

I have that raspy sound on mine also I thought its just exhaust gas passing through the manifold.

When I had the stock manifolds on that sound wus also there but it wasnt as noticable when I got mt LT's installed.

I always thought it wus normal.

That's what I thought too and didn't expect too much from a low priced LT header. Lived with the noise for almost a year. I'm starting to get tired of it and it's starting to become very annoying because part of my thought process always ask me, could there be a leak, weld broken, or even engine issue that I am not aware of. I know better next time. You get what you pay for I guess.

[GEEo]

Originally Posted by bmorecam

That's what I thought too and didn't expect too much from a low priced LT header. Lived with the noise for almost a year. I'm starting to get tired of it and it's starting to become very annoying because part of my thought process always ask me, could there be a leak, weld broken, or even engine issue that I am not aware of. I know better next time. You get what you pay for I guess.

I just got my car tuned this weekend and I've been driving the car for a day now and for some reason the sound is gone. even if I try to make the car replicate the sound.

I asked my tuner over the phone if I had any leaks or anything on the exhaust and he said no. Also didn't notice the sound I wus hearing.

Maybe we're just to paranoid about our car bro? lol

[J_Vibe92]

Reviving this thread because i have noticed the exact same issue. and its only during a 2k to 3k acceleration and in the beginning of my drive. it seems to go away after it heats up a bit.


by the way... why is this in the v8 section? this is for the v6 LLT

[need4spd]

Originally Posted by bmorecam

That is one place I didn't check. I'm going to check that area first thing tomorrow. There's definitely no leaks around the top though. I been dealing with this noise for almost a year and I'm sure if there was a year worth of leak there should be some black soot but nothing.

Also, I just want to clarify that is not a rattle like a heat shield loose but it's more of a hiss mixed with a hand shaker instrument like in the pic. It's weird even trying to explain the noise LOL.

I have the same noise. stainless power long tubes.. (noticed when you posted picture of the musical instrument..lol) We already searched for leaks and nothing. I guess its normal.

[Chevrolet Customer Svc]

Originally Posted by J_Vibe92

Reviving this thread because i have noticed the exact same issue. and its only during a 2k to 3k acceleration and in the beginning of my drive. it seems to go away after it heats up a bit.


by the way... why is this in the v8 section? this is for the v6 LLT

Hello J_Vibe92,

Sorry to hear of the concerns you're experiencing as I'm sure that's displeasing for you. Feel free to private message regarding this issue and I can explore these matters further.

William R.
Chevrolet Customer Care

[camguynj]

Originally Posted by bmorecam

I definitely used OEM gaskets. I really wish I could just do a quick header swap back to factory to confirm that it's the header but header swap on the v6 is not the same as the SS. It's a real PITA for the v6.

Does anyone know what would be another way to detect header leak other than visual inspection that I could do myself?

For external leaks...
1) Look under the hood at nite. You'll see flashes if/where there's a header exhaust leak.
or
2) Spray soapy water on the header, you'll see bubbles if/where there's a header exhaust leask.
or
3) Get a 3' hose. Put one end on top of each header port and the other end to you ear, you'll hear if/where there's a leak

You'll need to take them off to check for an inside collector leak.

[Jr305]

I have that same problem after my Long tube install. It sounds like a small piece of paper flapping in the wind when you moderately give it gas.

[Pro-tuned]

Originally Posted by Jr305

I have that same problem after my Long tube install. It sounds like a small piece of paper flapping in the wind when you moderately give it gas.

Check your cats, internals May have come loose.