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Replacing Catalytic Converter


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Hey guys, so I have a question on whether I should replace my cat or not. I have the P0420 code and honestly probably had the code for a good two years since I bought the car( 2009 Legacy 2.5i Limited.) About 6 or so months ago, i had my car being driven by my GF and all of a sudden the car didn't accelerate like it should've and was brought to a shop and had the cat "cleaned out" not sure what they did as the question wasn't asked how it was cleaned out but it drives and accelerates fine. Im thinking of buying an axle back exhaust and was just wondering if i should get the cat fixed/replaced first or just let it be, as its not really causing me problems. FYI, this is my first car. Car is at 148k.
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I would change all the O2 sensors first before touching the CAT.

 

The CAT is a pretty durable piece of equipment and I see way too many people replacing it when just replacing the Oxygen sensors (ALL of them) will make the car run more efficiently and in turn allow the CAT to remain healthy.

 

Also check your air intake for holes in the old accordion hose. It may need to be replaced and can contribute to triggering this code.

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I'd ask the shop what they mean by "cleaned out ?"

If he means gutted then you will never get rid of the code as the 2nd O2 will always be reading a rich exhaust as nothing was done to mitigate it.

A spacer may help but the rich exhaust will sooner or later destroy the 2nd cat.

 

O.

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Sounds like the cat clogged on your gf causing the poor acceleration. If you didnt seem to mind the light being on but wanted the car to run better, they probably gutted it.

 

Poor fuel trims can cause a fake cat code, same with a bad O2 or A/F sensor. I can't stress this enough, get a factory cat if that's what it needs. Otherwise, look forward to doing the job again in a year or 2. Aftermarket cats do not hold up.

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Sounds like the cat clogged on your gf causing the poor acceleration. If you didnt seem to mind the light being on but wanted the car to run better, they probably gutted it.

 

Poor fuel trims can cause a fake cat code, same with a bad O2 or A/F sensor. I can't stress this enough, get a factory cat if that's what it needs. Otherwise, look forward to doing the job again in a year or 2. Aftermarket cats do not hold up.

 

 

Would there be an option of just removing the whole cat and putting a pipe so it prevents there even being another clog? If so can you point me to that direction? I dont have emissions in Pennsylvania so it wouldnt really bother me.

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