Exhaust Noise Diagnostic

Stonehenge · March 28, 2019

I installed Corsa Cat Back, Kooks Long Tubes, and a Vibrant resonator. I have two noises I notice that I don't know if they are normal or not.

1. Under foot, I can hear the headers. It sounds like a faint rattle snake rattle; tis, tis, tis, tis.... more evident in V4 mode but still there in V8. I believe it is just the thinner stainless headers amplifying the sound of the engine exhaust. Am I correct or is this something I should be concerned with?

2. When I get on it, not necessarily WOT but get on it fairly well I sometimes(it's sporadic) hear a very high pitched bee buzzing sound. The exhaust has a deep rumble but when this occurs it's sounds almost like a bad high note from a trumpet. I am not sure what it is, has anyone experienced this before?

3tspapat · March 28, 2019

Are you certain there are no leaks whatsoever? Yes the headers can make the noise you've described but just because they can doesn't rule out any leaks. Also, check for soot around your exhaust flanges. If there is a look it will show soon enough.

Edited March 28, 2019 by 3tspapat

Stonehenge · March 28, 2019

I am not certain. I called the exhaust shop and I am going to bring it in in the morning to have them take a look.

Stonehenge · March 29, 2019

Took it by the exhaust shop this morning.

1. No leaks, this tis, tis, tis, noise is infact just the long tubes ampliphying engine noise.

2. Unable to locate any leaks, rubbing, or install errors. The believe it's the muffler. Corsa has no baffling material and they believe when it reaches a certain frequency with the RPM's this buzzing noise is coming from the muffler. Odd thing is it didn't do this before adding the resonator. But oh well.