i can assure u that this is not normal for the guy saying this is..i have used numerous different high flow cats and test pipes with aftermarket exausts and stock exhaust and never had a rattle sound..u must have something rattling around on decel..get under and shake the **** out of the test pipes and the rest of the exhaust and duplicate it and track it down...rasp is one thing..something banging metal to metal is not normal

 

Like others have said, the rattling is probably the heat shield or rasp if you're not used to hearing it. If you have a stock exhaust (or even aftermarket, I guess), it could be a muffler width piece that looks triangular from the side that's there purely for aerodynamic purposes. That thing comes loose and rattles a lot.

As for the CEL, you just need a non-fouler. You can get a mechanical one that just raises the sensor away from the piping, or you can get an electronic one. They both do the same thing, and they both work great. Only the electronic one, well, it's electronic so it can and will eventually burn out.

 

OP, does the noise sound like this?

First heard at 0:33 in.

http://youtu.be/Qxn2_54EXDQ

Edit:

Blah. I forgot how to embed videos on GDriver. I'm used to doing it on another forum.

 

Does anyone know how to get rid of this noise? Would a 2.5in Y-pipe solve the problem? Or is it the headers?

 

I've heard the noise will be reduced if you get a Y-pipe. Not sure about the headers.

I think the sound is kind of amusing. I've had a few ricer kids ask if it was my "blow off valve."

 

No doubt it's amusing to hear what other people think it is. In fact, my ricer friend asked me if it was my wastegate....

Anyway, I think I'm going to get a y pipe to try and get rid of it. Anyone recommend the Megan y pipe?

 

Megan's test pipes are decent. I don't know about the quality of the y-pipe. A piece that big, I'd suggest Motordyne or another company that uses quality parts.

Things like test pipes are a dime a dozen, and aren't expensive to replace if they rust through. Y-pipe is a bit of a different story.

 

so what was the answer, I have the same issue but already tackled and tested all of the mentions. No shield, no bolts, no nothing but a mystery rattle and a constantly leaking flange between TP and manifold .. Seems to be the manifold.

I was even gona change the stock resos.
I have a 2.5" Y pipe with the TP, and ultra quiet resos for mufflers. Rest is stock.
the rattle is still there, I even heat wrapped it, helped abit with the rattle...
can never figure it out 😭

 

sorry but the answer is that its a cheap test pipe and the rattling is coming from the material inside the resonated portion

 

Sorry but that's not the answer.. I don't have resonated test pipes. I also have the flex joint str8 piped and it's 2.5"

The test pipes are from z1 they are said to fit on stock exhaust so apparently that's bogus.
But they should be good quality...
Are you telling me that it's z1 TP that make that rattle on decel?

I hope someone else can chime in because frankly I don't think you have the answer..

 

So I had Nismo headers installed with 1320preformance open Test pipes ( resin free cats)and am running a true duel exhaust ending in the back HKS rear tuned exhaust NOW, For one check engine Light is get yourself (4) 90° O2 extenders/adaptors 2 up stream and 2 down stream and (SHOULD) eliminate CEL coming on. Now your noise in a manual MT-6 when changing out factory cats BETWEEN the.L & R side you have a metal (boomeroang) looking bracket that secures the OEM exhaust Cats, which are useless when running, HEADERS, TRUE DUALS TO TAIL PIPES,
so under accelerator heavy, light or a torqued turn L or R you have a slight exhaust hit at a certain point. It'll take a while. Look for a raw.mettal.thats been touching and when locate it install fire proof padding thick enough that it wont fall out and eventually will wear away and.then just repeat again. No big deal. Just play with your girl and youll find out all about her little finicky quirks and like a real woman find out her.issues and try to prevent any future complaints.🤪