Hi, i wanted to do my homework before i ask you guys, but can't really think of a word describe my sound. It only happens when i am revving up starting from around 4k, and it sounds like a ball rolling in a metal pipe or buzzing. it doesn't sound when i am driving low rpm, or even in highway. The car has high flow cat installed by previous owner,and the sound is coming from the back not the engine.

 

my guess is the honeycomb of the cat is busting up and a piece is in the exhaust rolling around.....

 

if that's the case, will it harm my car if i do not repair immediately?

 

if it were me, i would take down the Y pipe and get it out...

 

Only at or above 4K? Do you hear anything if you just roll? Metal ball in a pipe/buzzing would make me check wheel bearings first.

 

^^ He say's he is just revving ^^

 

Maybe it's the sound of schoolgirls getting wet from your exhaust tone.

 

lol fk, I guess it would help if I read past the first line of his post.

 

Starts from 4k ish. And when I shift it doesn't sound until it reaches 4k in next gear.And I drove today and buzzing is closer word for description than ball rolling sound

 

Lol too bad it is not too much of beech magnet lol only guys like it lol

 

For the most part... But Ive had more than a few girl's give it the stare down with a broken neck too lolol

 

He said revup.

gaaaaaa

 

You could check the bearings. There isn't much in the back end that would explain sounds at certain RPM.

 

Guess will have to check that first them thank you

 

Yep our z is a sexy car but just bit menly I guess.

 

You know how to check them, right? Just checking so you don't start throwing parts at it.

 

i still say it the cat honeycomb breaking apart..... wanna make a bet syner?

 

Terms?

 

Yea If you don't mean other bearing other than wheel bearing

 

I will make sure i check that too, but wont be driving much since it is winter so will take y pipe off when weather get warmer.