Any suggestions? I've checked all the bolts... and I have no heatshields other than the upper heat shield... all the ones over the cat and b-pipe are gone. I banged on the cat a few times... don't recall hearing any rattling when I did that.

I don't ever recall a rattle before. I recently swapped back to stock... then back to my JDM header/SMSP cat again after smog... and now I'm noticing the rattle.

Seems to be coming from underneath the center of the car somewhere.

It only really comes when the piping gets hot... like a few minutes after the engine is warmed up. I don't hear it in the morning (my commute is really short... ~4 miles)... so it's barely warmed up by the time I pull into the lot. I only started to hear it recently when I roll the windows down at stoplight with cars on either side of me reflecting the sound back.

It's rather embarrassing Could it be the cat? I would think it would rattle regardless if it was cold/warm.

 

busted cat?

my busted car sound cat rattled for a while then it went away.

 

Did it rattle all the time? Or only when it was warmed up?

Mine's only when warmed up. The volume moves up/down depending on RPM... and I sometimes get a burning smell when I get out of the car if I run it hard.

 

do you have a resingnator on your B pipe? if so check that i seen a couple of them fall apart also.

 

Yeah its an SMSP/Carsound cat and SMSP catback.

I've never heard of resonators falling apart... just cats.

Would either rattle only when warmed up? I would think they would rattle regardless if the engine is cold..since air/fumes are going thru the pipes anyway?

 

mines rattle when i turn on my car....then i give it a little gas, it goes away? It only happens when i start the car

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by black cx &raquo;</TD></TR><TR><TD CLASS="quote">mines rattle when i turn on my car....then i give it a little gas, it goes away? It only happens when i start the car</TD></TR></TABLE>

my gsr does the same thing..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 98R-1144 &raquo;</TD></TR><TR><TD CLASS="quote">Yeah its an SMSP/Carsound cat and SMSP catback.

I've never heard of resonators falling apart... just cats.

Would either rattle only when warmed up? I would think they would rattle regardless if the engine is cold..since air/fumes are going thru the pipes anyway?</TD></TR></TABLE>

i was saying in general i seen the resignators fall apart, i wasnt saying i seen SMSP's fall apart, i just wanted to clear that up.

the ones i seen rattled all the time, they sound just like a bad cat. i dont know why the tempature would make a difference unless when the car cooled down the broken peices would fuse together then when they got hot they would break loose? thats just a guess.
if it only does it when its hot, id look under the car and with a glove on hit the cat and resinator and see if you can hear something in there rttleing around.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DontBlink &raquo;</TD></TR><TR><TD CLASS="quote">i was saying in general i seen the resignators fall apart, i wasnt saying i seen SMSP's fall apart, i just wanted to clear that up.

the ones i seen rattled all the time, they sound just like a bad cat. i dont know why the tempature would make a difference unless when the car cooled down the broken peices would fuse together then when they got hot they would break loose? thats just a guess.
if it only does it when its hot, id look under the car and with a glove on hit the cat and resinator and see if you can hear something in there rttleing around.</TD></TR></TABLE>

Oh yeah, I wasn't insinuating tht SMSP's fall apart either I swung it by a muffler shop. Turns out the rear joint/opening of the Magnaflow resonator is cracked all around. Going to get it replaced and hopefully rid her of all this rattling!