Rattle in my Cat. '98 TJ
 

'98 TJ 4.0L Manual

I've got an annoying rattle in my Cat converter at idle speed. Thought
at first it might be the headers. But with engine off, I can go down
under and bang on the Cat and clearly hear the rattle inside. Is the
Cat toast? OBCII finds no codes. Just had emissions inspection 2
months ago so won't be rechecking for a while. Any recommendations?

Re: Rattle in my Cat. '98 TJ
 

It's usually the heat shield on the converter or the ceramic substrate
inside the conveter. The heat shield can be removed but it's there to
keep the floor pan from getting too hot and the grass you parked on
from catching on fire. Sounds like you could let it go for a while but
eventually it's replacement time.

GTK wrote:
> '98 TJ 4.0L Manual
>
> I've got an annoying rattle in my Cat converter at idle speed. Thought
> at first it might be the headers. But with engine off, I can go down
> under and bang on the Cat and clearly hear the rattle inside. Is the
> Cat toast? OBCII finds no codes. Just had emissions inspection 2
> months ago so won't be rechecking for a while. Any recommendations?

Re: Rattle in my Cat. '98 TJ
 

It's usually the heat shield on the converter or the ceramic substrate
inside the conveter. The heat shield can be removed but it's there to
keep the floor pan from getting too hot and the grass you parked on
from catching on fire. Sounds like you could let it go for a while but
eventually it's replacement time.

GTK wrote:
> '98 TJ 4.0L Manual
>
> I've got an annoying rattle in my Cat converter at idle speed. Thought
> at first it might be the headers. But with engine off, I can go down
> under and bang on the Cat and clearly hear the rattle inside. Is the
> Cat toast? OBCII finds no codes. Just had emissions inspection 2
> months ago so won't be rechecking for a while. Any recommendations?

Re: Rattle in my Cat. '98 TJ
 

It's usually the heat shield on the converter or the ceramic substrate
inside the conveter. The heat shield can be removed but it's there to
keep the floor pan from getting too hot and the grass you parked on
from catching on fire. Sounds like you could let it go for a while but
eventually it's replacement time.

GTK wrote:
> '98 TJ 4.0L Manual
>
> I've got an annoying rattle in my Cat converter at idle speed. Thought
> at first it might be the headers. But with engine off, I can go down
> under and bang on the Cat and clearly hear the rattle inside. Is the
> Cat toast? OBCII finds no codes. Just had emissions inspection 2
> months ago so won't be rechecking for a while. Any recommendations?

Re: Rattle in my Cat. '98 TJ
 

The catalytic converter media has begun to break into pieces. That,
however, does not necessarily hinder it from performing its duties.

It may continue to function properly for many more years until the pieces
rattling around are small enough to escape the converter.

If the rattling bothers you there are replacement converters available at
your corner auto-parts store or can be installed by your corner mom and pop
muffler shop.


"GTK" <gkucera@yahoo.com> wrote in message
news:NpbRg.6655$tT6.1041@bignews7.bellsouth.net...
> '98 TJ 4.0L Manual
>
> I've got an annoying rattle in my Cat converter at idle speed. Thought at
> first it might be the headers. But with engine off, I can go down under
> and bang on the Cat and clearly hear the rattle inside. Is the Cat toast?
> OBCII finds no codes. Just had emissions inspection 2 months ago so won't
> be rechecking for a while. Any recommendations?

Re: Rattle in my Cat. '98 TJ
 

The catalytic converter media has begun to break into pieces. That,
however, does not necessarily hinder it from performing its duties.

It may continue to function properly for many more years until the pieces
rattling around are small enough to escape the converter.

If the rattling bothers you there are replacement converters available at
your corner auto-parts store or can be installed by your corner mom and pop
muffler shop.


"GTK" <gkucera@yahoo.com> wrote in message
news:NpbRg.6655$tT6.1041@bignews7.bellsouth.net...
> '98 TJ 4.0L Manual
>
> I've got an annoying rattle in my Cat converter at idle speed. Thought at
> first it might be the headers. But with engine off, I can go down under
> and bang on the Cat and clearly hear the rattle inside. Is the Cat toast?
> OBCII finds no codes. Just had emissions inspection 2 months ago so won't
> be rechecking for a while. Any recommendations?

Re: Rattle in my Cat. '98 TJ
 

The catalytic converter media has begun to break into pieces. That,
however, does not necessarily hinder it from performing its duties.

It may continue to function properly for many more years until the pieces
rattling around are small enough to escape the converter.

If the rattling bothers you there are replacement converters available at
your corner auto-parts store or can be installed by your corner mom and pop
muffler shop.


"GTK" <gkucera@yahoo.com> wrote in message
news:NpbRg.6655$tT6.1041@bignews7.bellsouth.net...
> '98 TJ 4.0L Manual
>
> I've got an annoying rattle in my Cat converter at idle speed. Thought at
> first it might be the headers. But with engine off, I can go down under
> and bang on the Cat and clearly hear the rattle inside. Is the Cat toast?
> OBCII finds no codes. Just had emissions inspection 2 months ago so won't
> be rechecking for a while. Any recommendations?

Re: Rattle in my Cat. '98 TJ
 

The converter on my K car rattled for probably 60-80 thousand miles while
all the time passing the pollution tests. It did quiet down quite a bit
when the heat shield finally 'fell' off with assistance..


"RoyJ" <spamless@microsoft.net> wrote in message
news:BDbRg.5135$UG4.297@newsread2.news.pas.earthli nk.net...
> It's usually the heat shield on the converter or the ceramic substrate
> inside the conveter. The heat shield can be removed but it's there to keep
> the floor pan from getting too hot and the grass you parked on from
> catching on fire. Sounds like you could let it go for a while but
> eventually it's replacement time.
>
> GTK wrote:
>> '98 TJ 4.0L Manual
>>
>> I've got an annoying rattle in my Cat converter at idle speed. Thought
>> at first it might be the headers. But with engine off, I can go down
>> under and bang on the Cat and clearly hear the rattle inside. Is the Cat
>> toast? OBCII finds no codes. Just had emissions inspection 2 months ago
>> so won't be rechecking for a while. Any recommendations?

Re: Rattle in my Cat. '98 TJ
 

The converter on my K car rattled for probably 60-80 thousand miles while
all the time passing the pollution tests. It did quiet down quite a bit
when the heat shield finally 'fell' off with assistance..


"RoyJ" <spamless@microsoft.net> wrote in message
news:BDbRg.5135$UG4.297@newsread2.news.pas.earthli nk.net...
> It's usually the heat shield on the converter or the ceramic substrate
> inside the conveter. The heat shield can be removed but it's there to keep
> the floor pan from getting too hot and the grass you parked on from
> catching on fire. Sounds like you could let it go for a while but
> eventually it's replacement time.
>
> GTK wrote:
>> '98 TJ 4.0L Manual
>>
>> I've got an annoying rattle in my Cat converter at idle speed. Thought
>> at first it might be the headers. But with engine off, I can go down
>> under and bang on the Cat and clearly hear the rattle inside. Is the Cat
>> toast? OBCII finds no codes. Just had emissions inspection 2 months ago
>> so won't be rechecking for a while. Any recommendations?

Re: Rattle in my Cat. '98 TJ
 

The converter on my K car rattled for probably 60-80 thousand miles while
all the time passing the pollution tests. It did quiet down quite a bit
when the heat shield finally 'fell' off with assistance..


"RoyJ" <spamless@microsoft.net> wrote in message
news:BDbRg.5135$UG4.297@newsread2.news.pas.earthli nk.net...
> It's usually the heat shield on the converter or the ceramic substrate
> inside the conveter. The heat shield can be removed but it's there to keep
> the floor pan from getting too hot and the grass you parked on from
> catching on fire. Sounds like you could let it go for a while but
> eventually it's replacement time.
>
> GTK wrote:
>> '98 TJ 4.0L Manual
>>
>> I've got an annoying rattle in my Cat converter at idle speed. Thought
>> at first it might be the headers. But with engine off, I can go down
>> under and bang on the Cat and clearly hear the rattle inside. Is the Cat
>> toast? OBCII finds no codes. Just had emissions inspection 2 months ago
>> so won't be rechecking for a while. Any recommendations?