# Catalytic converter



## panicosm (May 6, 2007)

Hello,

I drive an 2002 2.0L x-tail.
I had the catalytic converter changed under warranty in 2004 after the check engine came on.
Now the check engine is back on and the dealer says I need a new catalytic converter. 
Any known problems? I do not want to spent so much money to find out they are wrong!

Thanks


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## aussietrail (Sep 24, 2004)

Hi mate and welcome to the forum.

The xtrail factory catalytic converter is known to be the cause of major problems, mainly because of its ceramic construction of the core and side walls which have been known to disintegrate under high temps and the flakes finding their way into the engine and causing the damage.

There has been a recall about the catalytic converter and O2 sensor boss breakage in some countries (including Australia) and Nissan identified a number of them with this problem.

I'm not sure if your xtrail has one or two catalytic converters, but if there is one, it will be part of the headers manifold and to replace it, they will need to replace the entire headers manifold. The second cat. converter is located under the car (if you have it)

My personal preference is to get rid of the ceramic cat. converter all together and install a stand alone stainless steel one and it will last for life!


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## panicosm (May 6, 2007)

Is it easy to take out the cat from the manifold? I guess a universal steel cat would have to be placed where the second is. I went out to an exhaust workshop and they seemed reluctant to install a universal converter. 
The dealer had replaced the manifold cover with a new design, on the last service, to solve overheating problems (they said). Do you think that O2 might be damaged from overheat?

Thanks again


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## Terranismo (Aug 31, 2004)

The only way to take out the cat from the stock exhaust manifold is to break it off internally. If you splice the manifold the material will be severely weakened.


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## aussietrail (Sep 24, 2004)

panicosm said:


> Is it easy to take out the cat from the manifold? I guess a universal steel cat would have to be placed where the second is.


The easiest and safest way to replace the first factory cat, is to get a new set of headers/extractors which don't have the cat built-in and install the free flow stainless cat. instead of the second factory cat. under the car. If you don't have a second cat. the new one will still go there.



> I went out to an exhaust workshop and they seemed reluctant to install a universal converter.
> The dealer had replaced the manifold cover with a new design, on the last service, to solve overheating problems (they said). Do you think that O2 might be damaged from overheat?
> 
> Thanks again


What is the new manifold design that the dealer has installed? As far as I know, all QR25DE factory manifolds look the same and have the cat. built-in

Also, not sure what are the causes of overheating, but chances are the O2 sensor is busted and it is not giving the correct temp. reading to the ECU.

If your exy is suffering from engine overheating, then the dealer should look for the causes before replacing things. It has been reported on a number of xtrails in Australia that the radiator gets blocked at about 80,000kms due to casting sand and this will block the flow of the engine coolant and cause overheating as well as A/C cut off. If not fixed, this continued overheating will cause a blown head gasket eventually.


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## panicosm (May 6, 2007)

Thanks
FYI the error code is P0420


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## aussietrail (Sep 24, 2004)

panicosm said:


> Thanks
> FYI the error code is P0420


Yep, that is the error code for a problem with the Cat. System for sure and possibly dead O2 sensors as well.

HERE is a good explanation for you to compare to what you're experiencing.


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