# Question



## Guest (Oct 6, 2002)

hey, i have a question. many sources are telling me that i cant get a straight pipe for my 95 240sx? is that true? they say that the 95 and up need the cat for some air sensor monitoring the air flow blah blah blah. i see that you dont have a cat on ur 95 200sx, so i was wondering if u ever heard of that, or if that is not a problem faced by the 200sx? also, what could i do to replace the cat? will a high flow cat work with the whole sensor?


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## landlord (Jun 11, 2002)

i wouldnt recomend removing your cat. i removed mine and cut out the second sensor and my city gas milage went to shit and my car is running really rich! have a shop weld in an after market cat and a fiting for your second o2 sensor after the cat. im going to do this when i can afford to. have to get a header first though!


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## Guest (Oct 7, 2002)

well, when i installed my custom exhaust, they removed all the piping from the cat to the muffler, including the so calld hollow precat, and they just replaced the piping with 2.5" piping. I am not sure if they removed any O2 sensors, but i doubt it. if I decide to remove the cat and put in a high flow cat, would that affect the computer in any way??? since they all advertise that these cats have a space for the O2 sensor fitting, shouldnt that take care of it? also, i think its weird, but my check engine light does not go on anytime i unplug the sensor even. when i start the car, the check light comes on, but it disappears when it is supposed to stay on. if the check engine light doesnt go on, should i just ignore it and put on headers and a high flow cat?


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## landlord (Jun 11, 2002)

the same thing happens to me!!! everone tells me with no sensor my check engine light should come on and it doesn't!!! but i think the second sensor is programed for emisions so.... without a cat it may light up. im not sure.


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## Guest (Oct 15, 2002)

I had an exhaust shop custom make the downpipe for my car. They made the necessary threaded opening for the second O2 sensor. My car runs a little rich when i'm idling, but under WOT it leans out accordingly.


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