Stock manifold, Corksport midpipe, and stock cat-back. Midpipe has been installed for ~5000 miles.

Yesterday when I went to run some errands I noticed that my exhaust got louder and more drone-y. I thought that the midpipe's hanger might be hitting the chassis cross-brace as I had this problem before, but that is not the case.

The best way to describe it is that it sounds like increased drone. It is most noticeable between 2-5k rpms. It seems to disappear at higher rpms. It is also load-dependent. I really don't notice a difference when I'm cruising and maintaining speed, but if I step on the gas to accelerate, it gets much louder, and if I let off the gas, it gets louder.

No codes and I don't feel any power-loss. The day before this happened, I had to drive over a bad stretch of road with lots of bumps. On that drive, I noticed a metallic clang coming from the front of the car over big bumps.



Any ideas what might be the problem?



I plan on inspecting the underbody of the car and ensure the bolts for the exhaust are all tightened down. Is there a heat-shield over the exhaust manifold by any chance? I tried searching this board and other places trying to find the same sound, but I couldn't find anything that sounded like my problem.

 

Wait until the car is cold. Jack her up nice and high adn throw her on stands. Turn on the car and QUICKLY lay down and run your hand from the exhaust manifold down to the end of the midpipe to check for any leaks. You mentioned that you heard metal noises, just want to make sure you didn't crack a pipe or something.

No leaks? Then possible that the packing in the midpipe blew out. I dont know enough about the corksport midpipe to be able to solidify that claim though.

 

This ^ But also at the same time, have a couple buddies grab some rags and hold them over the tail pipes, blocking the flow. That will slightly pressurize the exhaust and will make leaks or cracks more noticeable.

 

Was it a clang or a rattle? If it was a rattle it might be your catalytic converter just disintegrated, which could also make it louder.

 

Actually using a couple of potatoes would be better.

Then you can do it yourself.

 

Ding Ding Ding!!! We have a winner!

So I jacked the car up and as soon as I took a good look at the resonator, I saw some fiberglass packing sticking out of the edge of the resonator canister. After a closer look, it appears that nearly the whole out lip of the canister has broken away at the weld. This certainly explains all the symptoms I described.

I sent a warranty claim through Corksport's website and have had to play some phone-tag right now due to my work schedule, but hopefully I will hear from them soon and I hope this is covered as I've only had the pipe on since spring and have maybe put 5k miles of normal driving on it.

Pic of the damage. You can see the fiberglass packing sticking out pretty easy, and if you look at the edge, you can see the broken metal lip hanging out from the canister body:

 

Well that's interesting. Glad you figured it out, and GL on the warranty.

 

So I wanted to update this thread with a final resolution. Corksport was pretty quick to reply to me via e-mail. Unfortunately, that e-mail landed in my spam box which I rarely check. A couple more phone calls back and forth and we finally got things figured out.

Basically Corksport said that judging by the pictures I sent them, the welds on the resonator didn't penetrate properly (This diagnosis was confirmed by my welder.). Corksport was willing to cover up to an hour of their shop-labor rate and have me get it fixed locally or I could send it out to them (They pay shipping) and have it rewelded in-house. I chose to have it done locally as my friend Bryan at BTEK Fabrication is a top-notch welder and was able to help me out.

After that, I just had to provide Corksport with a copy of the receipt and they cut me a check to reimburse my costs. Overall I was happy with my experience with their customer service.

As for the midpipe, it is repaired, reinstalled and I have been driving around trouble-free for over a week now.