Exhaust Leak

[96ss1664]

Originally Posted by KaBoom1701

Anybody know what the torque specs on the header bolts are?

GM spec is 18 but have read people range anywhere between 18-22 ft lbs.

[AquaSSRS]

Originally Posted by Mechzl1

My engine has a "tick" at idle that is not related to the headers. You can hear it from the wheel wells and under the car decently. With the hood pope you can't hear it. Thought it was a lifter but honestly doesn't sound metal on metal nor is it that loud but it increases with rpm. it drives me up a wall. Honestly hate it, it's prominent on the driver side front wheel well towards the back of my motor. I talked to a few other people and said theirs make the same noise.... car has 4500 miles on it

My car has the exact same noise. Not sure if it is an exhaust leak or something else like the injectors or lifter noise. Once I get it in the air to install my wideband kit I will check it out. It is definitely more pronounced on the driver side.

[Mechzl1]

Let me know what you find, everyone else who has the same sound has told me they gave up trying to figure out what it is

[hotlap]

I've owned three cars with headers (not the Z) and they all had the ticking exhaust leak sound. Changing gaskets and torquing helps for a while but it comes back. Best I had was with copper gaskets but that would be a problem with aluminum heads and block.

[jayno20]

Any sound clips of this problem?

[Fulton 1]

Originally Posted by Mechzl1

My engine has a "tick" at idle that is not related to the headers. You can hear it from the wheel wells and under the car decently. With the hood pope you can't hear it. Thought it was a lifter but honestly doesn't sound metal on metal nor is it that loud but it increases with rpm. it drives me up a wall. Honestly hate it, it's prominent on the driver side front wheel well towards the back of my motor. I talked to a few other people and said theirs make the same noise.... car has 4500 miles on it

Mine also makes this tick noise and your description is 100% accurate for me as well. For reference, mine is a 2013 with only 2900 miles and all stock except for a Roto-Fab CAI.

It's hard to isolate exactly where the noise is coming from, but I hear it best with my ear just behind the driver's side tire and under the car or right by the wheel well. With hood open and engine running I can clearly hear the injectors and that's not it nor is it the "jar of marbles" sound that the blower coupler makes (I had my blower replaced under warranty some months ago so that noise is thankfully gone). Sounds almost like it's coming from the lower, aft side of the engine, but it's not a "bottom end" sound. More of a tick sound - not a classic exhaust leak sound, but something like that.

I can only really hear the noise at idle and it doesn't immediately show itself upon a cold start. Seems to need to warm up a little bit to make itself heard. I notice it most when in the garage or a parking structure where you get some sound reflection and standing beside the car. I cannot hear it from inside the car or while driving even with the window down.

I've only recently noticed the noise and decided, just to be safe, to pull off the valve covers and check for a bad valve spring. I did that last night and everything looked good - springs all in one piece and rockers tight. Nothing out of the ordinary.

I'll climb under there this week and check the factory exhaust clamps. Will also try and get a video of it if possible.

FWIW, I was poking around on youtube and this guy's exhaust leak is the closest noise that I could find to it: https://youtu.be/dqBuJKtzgc8

[Whos_Drivin]

Originally Posted by Fulton 1

Mine also makes this tick noise and your description is 100% accurate for me as well. For reference, mine is a 2013 with only 2900 miles and all stock except for a Roto-Fab CAI.

It's hard to isolate exactly where the noise is coming from, but I hear it best with my ear just behind the driver's side tire and under the car or right by the wheel well. With hood open and engine running I can clearly hear the injectors and that's not it nor is it the "jar of marbles" sound that the blower coupler makes (I had my blower replaced under warranty some months ago so that noise is thankfully gone). Sounds almost like it's coming from the lower, aft side of the engine, but it's not a "bottom end" sound. More of a tick sound - not a classic exhaust leak sound, but something like that.

I can only really hear the noise at idle and it doesn't immediately show itself upon a cold start. Seems to need to warm up a little bit to make itself heard. I notice it most when in the garage or a parking structure where you get some sound reflection and standing beside the car. I cannot hear it from inside the car or while driving even with the window down.

I've only recently noticed the noise and decided, just to be safe, to pull off the valve covers and check for a bad valve spring. I did that last night and everything looked good - springs all in one piece and rockers tight. Nothing out of the ordinary.

I'll climb under there this week and check the factory exhaust clamps. Will also try and get a video of it if possible.

FWIW, I was poking around on youtube and this guy's exhaust leak is the closest noise that I could find to it: https://youtu.be/dqBuJKtzgc8

Add me to the list...mine has that same noise, let us know if you find anything. It's annoying...

[2013 ZL1 #7860]

Use high temp rtv on the clamp.