I solved my CEL P0430 (Cat Efficiency Below Threshold Bank 2) by:

(A) Using an 02 simulator

(B) Buying a new precat $1000+Labor

(C) I Never fixed it because I like the light...screw passing smog

(D) I haven't solved it because I don't know how...where's bank 2?

(E) Lucky enough to be under the emissions warranty. I'll tell you what they replaced...

 

is this multiple choice? where is none/all of the above?

Anyways, my guess is . No really. I say A - o2 sim.

 

See what you need to do is put in header and a test pipe before you burn it up.

 

Change the O2 sensors and don't think about the cats.

The O2 simulator path will buy you some time but then eventually you will be hit with heater and voltage codes. The O2 sensors or the ECM (or both) are intelligent I guess, if you don't take the o/p of the sensor, there is some feedback from o/p vs heater and power lines.

I got these codes when I had 95K or something like that on the odometer and replaced all O2s. I haven't had any cat/O2 codes for almost 20K miles. Go with www.ngk.com the sensors come with connectors etc.

 

I failed inspection three weeks ago for this very code.

Installed O2 sims two weeks ago, cleared codes

Drove around to clear the ECU memory

Passed emissions at inspection 37 minutes ago.

 

How much did that cost? The site only lists spark plugs (iridium). Do you
Do you have part numbers? I have a 170k now.

 

State Inspections, bah, I remember doing them when I lived in Va and Mass. Glad Oklahoma don't care about what the hell drives on their roads.

 

Smog is a problem in LA. There's lots of Oklahoman wannabe actors polluting it up with me The smog makes the sunsets look weird sometimes.

 

I got the 4 O2s (California Spec) for $330. BTW, this company is LA based so if you order you should get is real fast. Very good service, prompt and the sensors work like a charm.

BTW, on the website towards the left under Product Search it defaults to plugs but there is a pull down menu for O2s (I just tried it now).

 

I havent solved my P0430 yet !!


00Maxi.... whats the right answer then? HELP ME !!!!


That NGK website gives 4 O2 sensors:


NGK OE identical O2 senso FRONT LEFT Non-California $99.85
NGK OE identical O2 sensor FRONT RIGHT Non-California $99.85
NGK OE identical O2 sensor REAR LEFT Non-California $108.85
NGK OE identical O2 sensor REAR RIGHT Non-California $108.85


for a total of approx. $400.... does that sound right??!!! WTF?!

Should I replace all 4 O2's for this code or mostly likely it is the rear or front?!!



TIA

 

Doesn't sound right.
Non-CA speced vehicles have 3 sensors, not sure where the fourth came from. Call the 1800 # and clarify!!

 

One mechanic told me that if this was a Sensor issue then there would have been a different code. If someone has a list of all codes and can post these here or online, would be nice.

I dont think it is all that necessary to go all out and replace all 4 sensors, because a) still no guarantee it will fix the problem, b) it costs a pretty penny. It is a major repair considering most early 5th gens are now are $5K cars.

Personally, I would like to replace that precat, or Bank 2, which is a short pipe, connecting the manifold (headers) to the catalytic converter. That part isnt cheap either, and makes me think if spending $1000 on a $5000 car makes sense.

 

You know, in this forum you can open threads with polls lol.

I'd say "A" is the best one.

 

http://forums.maxima.org/showpost.ph...&postcount=100

 

If you have an O2 sim AND leave the secondary O2 sensors plugged in (or you simulate the heater circuit with the right resistor), it will not throw heater codes. There are many here who have O2 sims for extended periods of time and do not have the heater or resistance codes. Obviously, this is assuming the sim is working and installed correctly.

 

Geez man... trying to give me a heart attack?! Dont tell me these things... I cant afford this kinda of money right now... give me some GOOD news...

 

Dealer solved it at 72K replaced cat....but charged me for the 02 sensor

 

Damn... this code seems to haunt a lot of people... here are a few links about it:


http://www.obd-codes.com/trouble_cod...old-bank-2.php


http://www.obdii.com/ubb/Forum1/HTML/002566.html


http://forums.maxima.org/printthread.php?t=405639


http://autorepair.about.com/library/faqs/bl736h.htm


http://www.o2simulator.com/24803.html

 

Yeah, that sums it up best.


No its not necessary and it won't solve the P0430 problem, I know from first hand experience. The used car dealer changed my o2's for all 4 free when I got my car. The P0430/P0420 remained. But I aslo had high voltage codes which were fixed.

 

so what fixed it?!

(please dont tell me u changed ur cat)

 

Dude, just get the O2 sim and be done with it.

 

I am in the same boat man with P0430. My car is due for emissions inspection around Febr-March '07. I remain skeptical of 02 sim because of uncertainty on how can this cheap solution can make things worse. I am for finding cheaper way to replace the precat

 

I am RIGHT there with you and I've read about this a lot.

Some more input on things I found out today: I called the guy that sold me my OBD reader and he wrote the whole software and he is pretty helpful. He told me that this cold could be either: O2 sensor AFTER cat failing to read cat OR cat itself.

My program can test the outputs from O2s and even test Cat efficiency. He told me to run the tests in order to determine if my issue is CAT or O2 sensor.


Now, IF the issue is the CAT, I have 4 options:

1. replace cat with Nissan cat = $$$$$
2. replace cat with high flow cheap cat = $$$
3. install O2 Sim and leave bad cat in = $
4. remove cat and install O2 sim = $$


why would I remove my cat, one would ask? Because if the cat is bad and IF it is clogged up, it could be the cause of my bad mileage. Most comments on no-cats NOT adding HP is correct, BUT most people forget that a BAD cat can affect performance.



Now this weekend I'll run the tests and i'll try to figure out which is the problem: cat or O2, THEN i'll decide which way to go.


hope it helped you a little bit.


later

 

Edit: 3 options. There are no high flow cats for the pre-cat. Unless your referring to the main cat behind the drivetrain, then carry on. Also, if the car is Cali-spec, it doesn't matter anyhow since the main one is not monitored.

Hell f'in naw. o2 sims is what. But yeah, get to testin man. Results will be helpful since this is such a notorious problem

 

finding the precat (Bank 2) is the key....Does anyone make those besides Nissan?

 

I too have a PO430 code, have replaced the Bank 2 rear O2 which did not fix the problem thinking of going the O2 simulator route unless I can find a reasonably priced PreCat. Regarding the O2 simulator where have listers installed it so that it does appear obvious if the inspector does a visual check?

 

just found out that I have a Cali Spec Maxima...


Dunno if this is bad or good... I remember reading about a TSB for a P0430 for Cali specs... but mine is already 85K miles....


Damn it... all was going SO PERFECT with the car....

 

I know there is a TSB for a P0420 on Cali Spec Maximas but is there a P0430 TSB? I have both codes. An ECU flash should take care of the P0420. I replaced the bank 2 rear O2 sensor in hopes that it will take care of the P0430.

 

Who's had replaced the precat- how much did you pay?

Do you guys think place like Budget or Cattman could custom build a new precat and we'd have a group buy special on it? Does anyone have any means of contacting those companies to see what solution they can offer. This bank 2 POS is just a tiny piece of a bent exhaust pipe with holes for 02 sensors, why does it have to be so damn $$$

 

Yeah, I had the P0420 code pop up on me about a month ago. Dealer took care of me for free by updating the ECU per the TSB. Car ran fine afterwards, but recently I had updated my MAF to the newer one and my gas mileage is crap now. Got a take a trip back to the dealer to get the ECU updated again because of the new MAF . But, as far as the P0430 code, there isn't any TSB as far as I know. It's just about trial and error in knowing what's actually throwing the code.

 

Maybe you are right, I've read something about EITHER P0420 or P0430 for Calis....


And if you guys are affirming it is P0420 then you are right, I cant trust my memory because I read about it few weeks ago...



So then I am back to step 1.....

 

For those who have replaced the bank 2 precat:

A Nissan dealer quoted me $989 for the part + installation.
autopartswarehouse.com has an aftermarket replacement for $406.
Amazon seems to have the same one but it's out of stock.
Does anyone have DaveB's price handy?
Other choices?

Thanks

 

You can usually find some in the 5th Gen Classifieds.

Sloppymax has his OEM exhaust manifolds and y-pipe for sale in the Classifieds: http://forums.maxima.org/showthread.php?t=494436

 

ODB- Dave B is charging about 470 for it.

It is very hard to find smthg like this in classifieds because ppl usually leave their stock precats on and replace aftercat (ypipe)

Can someone post phone numbers to Budget, Cattman, Stillen, and whoever else is manufacturing exhaust for our cars.

 

To those in Massachusetts - Lou's Custom Exhaust just quoted me $436 for the Eastern aftermarket bank 2 precat (including installation)

 

I changed my bank 2 pre-cat out. Luckily I got a used one from someone on here. Cost $75 and I installed myself. Wasn't too hard of an install, except the normal rusted/frozen bolts.

My P0430 code has been gone since then...about 20K miles ago.

 

Okay, resuming the whole topic: I have the P0430 and Cali spec maxima.


Which O2 simulator to buy and which O2 sensor to connect to?


I just realized I have 4 O2 sensors and I am not even sure if the O2 Sims are all the same, so I am afraid about buying the wrong O2 sim.



thanks in advance

 

Two of the sensors, you have no need to touch. They control A/F ratios relative to each bank. The ones you want are below/after each pre-cat. Here is a picture I found from an org member which applies to Cali-spec o2's.

 

Thanks a TON bro!! Really!


Now last question: are all O2 sensors on my car the same, Or I have to shop for a specific O2 Sim? Or they only sell one type of O2 Sim that would replace any O2 sensor in the car?

 

No problem, you'll be happy when that yellow glow is gone.
The o2 sims are universal. It's a single unit either in single output for just one bank, or in dual output for both o2s. Just visit o2sim.com and get your read on and go from there. Or make your own. This is from an org member.

http://forums.maxima.org/showthread.php?t=481430