When cold, at startup, my Borla has a very loud metallic tap, tap noise emitting when I pull away steadily to 35mph. Almost sounds like an exhaust leak, checked all connections(good), bolt torque (good at 32-35 lbs) and other common sense possibilities.

Once warm, no loud metallic noise is present. Do you think it is the sound packing in the Borla exhaust causing the noise? It gets worse now that the temps have dropped to below freezing.

Dealer said it was 'normal' resonance for this exhaust and that his Toy w/Borla has 125,000 miles and no problem, yada, yada, yada. I am happy for him, but it doesn't eliminate my problem. Any suggestions?

 

I remember this being covered here before and it is normal.

 

Sac State,
I was able to fix my borla rattle problem by removing the two bolts connecting the muffler to the cat and re-seating the cat gasket (fits inside the muffler pipe) and flange (metal ring around the muffler pipe with 2 bolt holes). Another forum member had the same problem but I don't think he was ever able to fix it. Maybe I just got lucky? It's been about a month since I fixed it and the rattle hasn't come back yet...

See the other thread I started about my problem:

https://www.yotatech.com/forums/show...ighlight=borla

 

Thanks Jordan, I was hoping to not have to take apart the connections, the previous posts on this subject, I don't believe, were being effected by the extreme cold, just daily driving, which I don't seem to have, just when it is extremely cold or a front is passing.
And the other posts mentioned connection leaks, I was asking about the internal packing within the muffler needing to be warmed up first before it mellows out.

 

jordan,


that was me...and the second time i did it it worked...this time i completely unbolted the connection to the cat and turned the flange around 1 time and then bolted it back on...now it is gone...hopefully it will last...i feel like we are gonna have to do this every month or so...lol

 

Sac State,

Its weird, i started to get this when it was getting colder out and even underneath the truck with it running I couldnt pin point the sound...at first i thought it was actually something loose in the cat itself causing the rattle, but once i unbolted the connection and put it back it was gone...the noise was just a metal sounding vibration/clank...but that fix worked...good luck


Brian