My exhaust is starting to make a fluttering sound but its only coming from the left side? More pressure comes out from the left side also. Do you know what it might could be? The cats?

 

Probably. Year, mileage, and stock or aftermarket? Details help when doing internet diagnoses'.

 

I don't think it would be the cats if it's just one side of the muffler. The stock setup is not a true dual and it's just one pipe from the cat.

 

2003, 160,009, aftermarket exhaust. But before I changed the exhaust it was the same thing wiyh the stock exhaust.

 

Would probably get a better answer if you posted a video. or even a sound clip. i noticed with the stock exhaust the driver side tip always has more exhaust coming out of it.

Need a little better description too, is it all the time this sound happens? is it only on decel? around a certain rpm range. all these will help get a more accurate answer.

 

"fluttering" sound could be an air leak. if you've changed exhausts and it still does it, probably where the cats meet the Y-pipe.

 

^This

 

http://www.ebay.com/itm/200851763152...84.m1439.l2649 Or it could be a crack..

 

If your still single out i would check the flex joints. both mine failed at the same time and it sounded like a rattle. But turned out they sucked air in causing the noise on decel. if a cat was bad you would hear rattling as well because the stuff inside is broken up.

 

Maybe someone shoved a potato in one of the pipes