22 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
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YOUR RESEARCHbad cat!
Leading reported evidence
Replace last month
Performed · outcome unconfirmed
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0
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0
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1
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Read evidence and context
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Performed · outcome unconfirmed
I got mine changed last month under the car warranty.
Leading evidence: 'Replace last month' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'muffler first' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Replace last month' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Performed · outcome unconfirmed · Original poster
So far consensus seems to be to buy the best used cat I can.
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Performed · outcome unconfirmed · Original poster
Well about 4 hours and a half grand later and my new/used cats are installed.
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Performed · outcome unconfirmed
Cheapest option is used OEM, as others have noted.
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Suggestion
I've talked directly with one of the well-known aftermarket suppliers and was told that their experience is the cats won't stand up to even moderate track use (i.e., DEs).
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No, my feline is behaving fine, it's one of my catalytic converters that's giving me grief.
I took an aggressive romp on the back roads - just whipped the car for 3 hours straight, and when I was done my left side cat was rattling, vibrating inside. It's not throwing codes or anything, just buzzing real hard at 2000 rpm.
I put the car on a hoist and banged around with a rubber mallet. The mufflers on that pipe is a little rattly too, but it's my cat that's the problem.
So, please help me review my options:
1) Buy a new cat from Porsche - estimate $2K
2) Buy a used cat - estimate $1K
3) Buy a set of Fabspeed cats - $1.5K
4) Install cat bypass system - $unknown
Does anyone have any advice, better ideas, snide comments?
I think you can get a better deal than that if you search. I had a cat go bad and found a complete take-off system (2 cats, 2 mufflers and 2headers) from a guy for $800.00. They had less than 1200 miles on them and looked like new!
don't forget the cats have 8 years warranty, at least in the US..., your car is a 2002... might want to check it out. I got mine changed last month under the car warranty. parts and labor all free.
If not, used cat are coming often on craigslist, keep your eyes open.
OK -
So far consensus seems to be to buy the best used cat I can. That certainly seems to be the most economical option.
I have a PM offer already, so that looks to be the easiest option also.
Is no one is advocating for the Fabspeed setup?
Picked up a used set just this weekend (Thanks Ed). Mine lasted 88k miles on a 2002 c2. Used cats are much cheaper then you think. I missed out on a set on 6speed for $200....
Stock cats should outlast the low-cell-density aftermarket units. I've talked directly with one of the well-known aftermarket suppliers and was told that their experience is the cats won't stand up to even moderate track use (i.e., DEs).
The advantage of aftermarket "performance" units is their low mass.
Cat bypass will give you a check engine light (unless you figure out a way to fool the post-cat O2 sensor into supplying a signal the ECU can live with) and will pollute. Assuming you have the pre-cat O2 sensor set up properly, the engine will run fine.
Cheapest option is used OEM, as others have noted.
If you don't mind the sound increase, I would def upgrade to the Fab Speed if you're ok with the money....
but if it's not a "want" for you, spend half as much for a used cat would seem like smarter money
Well about 4 hours and a half grand later and my new/used cats are installed. The cats I found were off of a low mileage car and looked really good on the install.
Problem is, the noise persists,
which means my first inclination was correct. I'm pretty sure I have a bad muffler.
I thought it was the muffler first, then tapping around with a rubber mallet with my tech and it sure seemed like the cat was bad.
So....anyone have a good used muffler (passenger side)? I think I have a line on one locally here, but thought I'd throw it out there.
Sounds like you at least recoup some of the $ by selling your used but otherwise ok cats?
I am installing a new/used set as well this week, but both were throwing error codes so I know they are bad. I lived with a slight rattle until they went for sure!
Tim - no need to be sorry. My sh!tty diagnosing skills are not your fault. I'll email you in a bit here.
And yes - I might be able to sell my old cats. We'll give that ago for sure.
My first inclination thinking if it were me that had the problem seems correct. Get ticked off and drive nails in it to get even.
Some other thread made mention of brackets or joints can give a rattle. Its not always internals from what I recall.
well, the plan is to get it up on jackstands and then use a stethoscope to pinpoint the noise while a helper holds it at the magic 2000 rpm.
My money is still a loose baffle in the muffler.
Will post again.
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