Cat Converter replacement codes
#1
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My car threw out a P0421 and P0431 code. Is this something that I should immediately fix with a new cat converter or I can put it off for a couple of months? Also, how difficult is it to replace a cat converter?
#2
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How long have you had the codes? How many miles on te car?
To replace those cats you either buy the entire downpipe from the dealer at $1400 a side, or possibly dind an aftermarket downpipe for $500-$700, but not all engines are supported. I think it is only for the 2.8, maybe the 3.0 too.
You can also take the downpipes off, cut off the cats and get new ones welded on, and reinstal the downpipes.
This is not a cheap repair.
To replace those cats you either buy the entire downpipe from the dealer at $1400 a side, or possibly dind an aftermarket downpipe for $500-$700, but not all engines are supported. I think it is only for the 2.8, maybe the 3.0 too.
You can also take the downpipes off, cut off the cats and get new ones welded on, and reinstal the downpipes.
This is not a cheap repair.
#7
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What is the normal lifespan of a 3.0 catalytic converter in a properly maintained 2002 A4. We have 97K on ours and are told it needs one bank replaced and should do the other at the same time. 3K we'd rather spend elsewhere. Check engine light on dash threw the code at the local dealer.
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#8
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http://forums.evolutionm.net/evo-how...ouler-how.html
Do it on both downstream ones and you should be good for emmisiion
Do it on both downstream ones and you should be good for emmisiion
#9
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Either ignore the CEL and work around emissions by creatively setting readiness, or replace both cats.
The anti-fowler/rear O2 standoffs are not legal. They are a great idea...unless you get caught.
#10
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That sounds about right. One of the joys of ownership of the crappy 3.0 is low mileage cat "failure". And by failure, I don't mean that the car actually falls apart, it just loses efficiency until the CEL comes on.
Either ignore the CEL and work around emissions by creatively setting readiness, or replace both cats.
The anti-fowler/rear O2 standoffs are not legal. They are a great idea...unless you get caught.
Either ignore the CEL and work around emissions by creatively setting readiness, or replace both cats.
The anti-fowler/rear O2 standoffs are not legal. They are a great idea...unless you get caught.
I like how you put "not legal" word. I would say "not legal" starts at the moment when you are fully aware of faulty cat and begin to tamper either with aniti-foulers or "creatively setting readiness" But that's just matter of person individual conscience.
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In both scenarios you pass emission, but still polluting.
And now being serious. Yes they might check it. It really depends from person. I did mine in firestone. Guy didn't even bother. The truth about emmisiion is that shops don't get paid for it at all. All 25$ goes straight to state. That's why even brand names like firestore just do not care.