About 4 days ago I noticed a very strange noise coming from my exhaust. If the car sits and idles, there is a very loud buzzing/rattling sound that comes from the exhaust (muffler in the back specifically). It is not constant and happens at random. It also can be heard when driving as well. Right when the engine reaches 1800rpm the buzz is audible and once it goes past about 2000rpm the sound goes away. When the car reaches normal operating temp the sound dissapears completely. Any idea what is going on here?

 

there was another post just like this a few threads back.....appearently it is the fuel pump that causes this sound.

-justin

 

Yes, I saw that thread. The sound I hear seems to be more of a buzz rather than a hiss though. If it is the fuel pump does it need to be looked at or is it harmless? I've had the car for well over a year and the sound just started a few days ago.

 

if it is the fuel pump than yes it is harmless as this is what numerous other "problem free" z owners are experiencing. i guess it is possible that you are experiencing some type of loose element in the exhaust system though. i get a hissing, whisp type sound on deceleration between 2200 rpms down to about 1500 rpms. its been there since i added my borla exhaust almost 1 yr ago. i cant stand it but it seems its somthing ill have to live with unless i decide on swapping another exhaust, not likely though......what cats do you have?

-justin

 

I'm getting the same thing, I brought it in one time and they said they cou;d not find the problem... But i am going back though

 

Everything is stock except my intake.