PO430 and o2 sensor readings.

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My maxima has been throwing the po430 code now for a few months. I've been clearing the code but it keeps coming back on progressively faster after each code wipe. Decided to get the 02s readings and B1s2 B2s2 read 0.290 volts steady each. Bad front cat? any opinions.
 
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Could be a bad cat, had the same issue on my old Altima. I replaced the cat, still had the issue but the codes were throwing at a less infrequent rate. I did some more poking around, turned out I had a small exhaust leak (bad gasket) behind the rear cat. Crawl under that bad boy and check around before dumping money on a new o2 sensor or cat. BTW, stock exhaust??
 
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sasha

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Originally Posted By: lugNutz
Could be a bad cat, had the same issue on my old Altima. I replaced the cat, still had the issue but the codes were throwing at a less infrequent rate. I did some more poking around, turned out I had a small exhaust leak (bad gasket) behind the rear cat. Crawl under that bad boy and check around before dumping money on a new o2 sensor or cat. BTW, stock exhaust??
yeah stock. everything behind the rear cat are new. gaskets and pipes. Noticed the occasional rotten egg smell.
 
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Originally Posted By: sasha
Originally Posted By: lugNutz
Could be a bad cat, had the same issue on my old Altima. I replaced the cat, still had the issue but the codes were throwing at a less infrequent rate. I did some more poking around, turned out I had a small exhaust leak (bad gasket) behind the rear cat. Crawl under that bad boy and check around before dumping money on a new o2 sensor or cat. BTW, stock exhaust??
yeah stock. everything behind the rear cat are new. gaskets and pipes. Noticed the occasional rotten egg smell.
That being the case, I would lean toward a new cat, but maybe take it to an exhaust shop and have them check it out for you. If the flex pipe is in good shape, go with a universal cat and have a reputable installer do it. If not, than go on RA and purchase a direct replacement system like this one: RockAuto I will not tell you which brand to buy because it is YOUR money. But I can only tell you that I had purchased from Walker in the past and had to take it somewhere to have work done to get proper fitment. Bosal is the best for direct replacement IMO. Yes, more expensive, but IIRC they are OEM for Nissan's of the 2nd and 3rd gens.
 
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Originally Posted By: yvon_la
Imagine pennzoil ultra platinum pureplus with graphene .ya they use graphene thats for sure
What does this have to do with this thread?
 

sasha

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Originally Posted By: lugNutz
Originally Posted By: sasha
Originally Posted By: lugNutz
Could be a bad cat, had the same issue on my old Altima. I replaced the cat, still had the issue but the codes were throwing at a less infrequent rate. I did some more poking around, turned out I had a small exhaust leak (bad gasket) behind the rear cat. Crawl under that bad boy and check around before dumping money on a new o2 sensor or cat. BTW, stock exhaust??
yeah stock. everything behind the rear cat are new. gaskets and pipes. Noticed the occasional rotten egg smell.
That being the case, I would lean toward a new cat, but maybe take it to an exhaust shop and have them check it out for you. If the flex pipe is in good shape, go with a universal cat and have a reputable installer do it. If not, than go on RA and purchase a direct replacement system like this one: RockAuto I will not tell you which brand to buy because it is YOUR money. But I can only tell you that I had purchased from Walker in the past and had to take it somewhere to have work done to get proper fitment. Bosal is the best for direct replacement IMO. Yes, more expensive, but IIRC they are OEM for Nissan's of the 2nd and 3rd gens.
My car came back from the dealer 6 months ago and they said i might need a new cat. I usually take dealer words with a grain of salt. But looks like this time they were correct. I am looking at a bosal cat replacement. Once i get the $$$ for it i'll swap it out myself. This is actually my fault and mechanical fault of the car in a sense. A couple of months of coil pack failures and fuel injector failures More or less caused the front cat to either burn up or get clogged up. $500 F..N for a cat plus it needs a new ignition lock cylinder,.....money money money.
 
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Were the Maxima's roped in with the Altima's that would ingest the pre cat? Or was that only the 2.5 second gen's?
 

sasha

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Originally Posted By: michaelluscher
Were the Maxima's roped in with the Altima's that would ingest the pre cat? Or was that only the 2.5 second gen's?
just the 2.5.
 
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Originally Posted By: sasha
Originally Posted By: michaelluscher
Were the Maxima's roped in with the Altima's that would ingest the pre cat? Or was that only the 2.5 second gen's?
just the 2.5.
Correct, only the 2.5's. OP, since you already have all new gaskets and pipes behind the cat, just pick up a new one, or live with the SES being on for a bit, unless it's clogged, that will cause issues. I did that for a while before I touched anything.
 
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Originally Posted By: Miller88
What about trying to clean it? I think Scotty Kilmer has a video on that.
Not a good thing to do.
 
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Originally Posted By: sasha
Noticed the occasional rotten egg smell.
That's the dead giveaway right there. A strong indicator your catalytic converter is toast.
 
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Originally Posted By: lugNutz
Originally Posted By: Miller88
What about trying to clean it? I think Scotty Kilmer has a video on that.
Not a good thing to do.
Why not? Genuinely curious
 
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