i'm still on the original with 100k and a jrsc.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jabroni95gsr &raquo;</TD></TR><TR><TD CLASS="quote">i'm still on the original with 100k and a jrsc. </TD></TR></TABLE>


the rule of thumb is to replace it once it reaches 100k.

 

I've NEVER had to replace a cat.
'82 Rabbit 118k miles
'86 Jetta 147k
'89 Saab 220k
'95 GS-R 118k
my newer cars don't have enough miles to count...

It's easy enough to poison the catalyst early, tho. If you drive around for 6 months with a bad O2 sensor; or if you get something strange in your gasoline (too much sulpher?); run too rich or lots of misfiring & you can overheat it. Not all of those things are under your control.

Misfiring is bad. You have plenty of unburned fuel; plus there's unused O2 so the sensor thinks the engine's running lean. That can make the catalyst get REALLY hot.

 

a cat will last forever if the engine is running properly

 

I just passed emissions with 120k on mine

 

Is it possible for the internals to rattle loose? My cat or something in that area is rattling like hell.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by speedymon &raquo;</TD></TR><TR><TD CLASS="quote">Is it possible for the internals to rattle loose? My cat or something in that area is rattling like hell. </TD></TR></TABLE>
Much more likely that's a loose heatshield. But it's possible. The monolith is made of ceramic, just ask anyone who's poked a hole thru it.

 

The ceramic can crack and leave bits rattling around in the cat. I should know, that's my problem and it's very annoying

I'm on my 3rd cat; I basically have to replace it once a year to get through AirCare... this year I had to go 1.5X oversized to get through. Very friggin' annoying, but I'm too eco-friendly to go test pipe...