I have a 05 tl Base. ATLP j pipe with the third muffler cut out.
I have had this hiss before I did any mods. I put the j pipe on thinking that was the problem turns out it was not. So know I am clueless to what it could be. it sounds l like it is coming from the front pre cat, but I pulled it off and checked for a break in it, found nothing. Put new gaskets in and put it back togather still has the same problem. You can hear it worse when you first start the car then it will quite down and you can only hear it when accelerating at a moderate pace.
Any ideas.
I have had this hiss before I did any mods. I put the j pipe on thinking that was the problem turns out it was not. So know I am clueless to what it could be. it sounds l like it is coming from the front pre cat, but I pulled it off and checked for a break in it, found nothing. Put new gaskets in and put it back togather still has the same problem. You can hear it worse when you first start the car then it will quite down and you can only hear it when accelerating at a moderate pace.
Any ideas.