Does anyone know why my muffler produce fart-like sound (it's like sound is disintegrating and vibrating) when I run car when it is cold (by cold, I mean not driving car during previous 30 minutes or so). I can barely press gas pedal during this moment because if I do, that farting sound will come out, making my Tibby look like those cheap-muffler equipped Civic. This sound disappears after driving the car for couple of minutes, though.

So anyone know why this happens, and any solution to this? (If there is no solution, I think I will get new muffler).

 

Isn't that caused by unburned gas (running rich)?

I thought most straight-through muffler designs always had that sound, and when the pipes heat up, sound mellows out.

 

Strange...I know of 4 magnaflow equipped Beta's and none of them have this problem.

Question...do you have a resonator/glasspack? If not, that may be the cause...as All are running some form of "premuffler".

 

I have a Magnaflow with a 2.5 custom cat back.. No fart sound here.. Sounds nice and smoth, but breaks up a little at about 6K.. The intake more than makes up for that though.. Thing is loud as HELL up there.. Might just be the Magnaflow you have.. Mine is only 3" outlet..

~Matt

 

My car has 23" cherry bomb glasspack between the mid pipe. The fart sound definetely comes out at any RPM if I do not put any glasspack (but with 4-2-1 header). But I think this is different problem since it only happens during first few minutes...

 

alright im in the clear


BTW,... anything in your exhaust can change the tone of your exhaust,... try changing glasspacks

Im not sure how the cherry bomb one sounds,... but you might want to switch something and try it out

 

Mine works great and sounds good and Im an Automatic...I took out my catylitic converter though if that helps...

 

How old is your MagnaFlow?
Could it be because the fiber in the muffler kind of contracts when cold? And the when hot it expands, thus giving more isolation?
How cold is it where you live?

 

please dont remove your *only* cat

upgrade your cat to a high flow

Most of you dont recycle or conserve, at least do one thing for the environment

 

Well my muffler is one year old... and usual temp here in Santa Barbara is 70-80 F.

I am just using stock cat converter with 4-2-1 header.