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hello everyone

1695 Views 8 Replies 2 Participants Last post by  i68k
pre-cat prob, not sure how to exstend the downstream 02 senser!

got a 2004 Nissan Sentra SER Spec-V w/113k and just now really hearing about the precat prob! good news my light came on for the p0420 code, and i looked it up and found these forums and thanks to the people on here i pulled my precat off and it was just about to start happening! on the other hand nissan didnt even try to find the screws for the butterfly valves that came out years back! I took off my cat and out popped two little B B's and from what i hurd those were the screws! I love my car, But after that will never trust the dealer again! anyways ive got this far by DIY!
Thank You to those people that posted all the info for it! you were a really big help!!!:)
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Last edited by acespecv; Yesterday at 05:55 PM. Reason: P.s. Does anyone know how to extend the downstream 02 senser? going to put a aftermarket header on and move the downstream 02 senser behind the secondary cat! Any help whould be alot! Thanks again
the 04-06 already come with extended wires, your lower o2 is already on your midpipe. when you put a header on, you just need 2 antifoulers on the downstream o2, no need to extend it, it goes back in the same hole. otherwise, you must solder the wires for the o2, it is a voltage specific sensor.
hope you replaced the alt after you took it off.

you need to use 2 antifoulers on the downstream o2 sensor, thats the sensor on your midpipe in between the cats. this will prevent you from getting an ses light when using an aftermarket catless header.
....got a random misfire and drives like sh** and happened right after i took my precat and alt off....
you said you took it off with the header, just saying, hope you put it back on and the belt as well. if you start the motor without a belt or alt, it will misfire and run like ****, if it even starts.
look up information about the 07+ head gasket and 07+ head bolts, they are much stronger, if youre looking for aftermarket stuff maybe like ajusa headgasket and arp headbolts.
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