exhaust noise

[lking]

i hear a rattling noise its a faint noise not too loud coming from the front end of the car when accelerating between 2500-3000rpm i'm 99% sure its the exhaust(dual exhaust 04 LS) because i only hear this noise when accelerating at high rpm i checked out the exhaust and heat shields nothings loose everything looks fine cars only got 65000 kms so its in mint condition i started to hear this rattling noise after i floored the car about a month ago anyone got any idea what could be causing this noise?

 

[M4rk]

http://www.lincolnvscadillac.com/showthread.php?t=68621

 

[lking]

could it be possible that the inside of the catillac converter is rusted and is now making a noise has this ever happened before?

 

[SlickLS]

Do you have any mods that opened up the motor? You running 93 octane? Sounds like it could be spark knocking/pinging.

 

[ATrom]

Could possibly be the cat

 

[lking]

i always run premium gas NO mods a spark plug?....wouldnt that cause a rough idle the car idles so smooth u cant tell if its on or off (knock on wood)

 

[lking]

Could possibly be the cat

if it is i gotta find out which one i cant put it on a jack and listen to it the car doesnt rev over 2000 in park

 

[ATrom]

if it is i gotta find out which one i cant put it on a jack and listen to it the car doesnt rev over 2000 in park

What I would do is just try and rattle them and see if you hear anything

 

[mrshl13]

Check the straps welded between the pipes before and after the resonators ESPECIALLY if you've ever bottomed out. I think that's what caused mine to break. I posted pics toward the end of the linked thread.