Anyone knows whats this SES for
P0430 Catalyst Efficiency BelowThreshold (Bank 2)

Thanks for any help in advanced.

 

Sounds like you need a cat. How many miles is on your car? By law cats carry a 80,000 mi/ 8 year warranty.

 

go to dealer. They will reprogram your ecu. it that doesn't solve the problem thay will change the catalyst. all of them are covered by state law.

 

Interestingly enough, my car, a 2000 SE, just threw the same code today. After reading a bunch of past threads on it, the problem is usually cleared up either with an ECU reprogram with the latest updates, or a new cat.

However, what I don't understand is which cat bank 2 corresponds to. Hopefully someone else can chime in and help with that one.

 

Thanks for the help guys.
I been having problems with the car for the past few months first the throtle b.. then the coils and when i thought that i finally clear the SES for more than 2 weeks, i get this SES. My car has now 115,000 miles so no warranty.

 

Ride,

I just repaired my p0430 SES. It require a new o2 sensor and a cat....not a cheap repair. The dealer quoted 998 to replace just the cat. 700 for the cat and 300 labor. I wisely called Dave Burnette and purchased the cat for 460 and he told me it should take no more than 1.5 hours. A shopped the labor around to various dealers until one quoted the job properly. I ended up paying 650 for the cat and around 180 for the o2 sensor. My car didn't require a reprogramming of ecu....that's for specific vin#'s. Good luck

 

Yeah I had that code also. Never got a P0420 for the other pre cat though, just P0430. It was there for about 4 months and I eventually started to get that rotten egg smell. Instead of spending that money on 1 pre cat, I purchased some o2 sensor simulators, did a Fed-spec conversion with y-pipe, cleared the codes and they never came back. Car has 131,xxx miles.

 

thank you for the info dougb and yayomax.

Now I remember that about 3 weeks ago my suspension was bad and the car was bouncing everywhere specially on bumps and like 2 times i kind went to fast on a bump and the car hit really hard on the bump two weeks later i got the SES i think thats what cause it.

 

dougb,

Do you know which O2 was bad?

 

The rear o2 sensor was the bad one. I had replaced the front one a while ago.

 

IMO the first line of fixing P0420/P0430 is replacing the O2 sensors, I did mine and haven't had codes for sometime now. The possibility of the pre-cat or cat breaking down does exist but not as much as these O2 sensors. There are a lot of threads related to these codes and multiple fixes have been proposed (some of which I had tried) but then replacing the O2 sensors is something to give a serious thought!!!

 

I wouldn't replace the o2 sensors unless they were diagnosed as being bad. Why pay 300-400 to replace parts that are working? The Consult II will provide the readings for the sensors. Once I replaced the rear o2 sensor the p0430 code didn't come back on for about a month. At that point I replaced the cat. So far it's been about two weeks without seeing the SES light.

 

Usually an 02 sensor on our cars don't go bad that often. Something like a GM... YES, but us NO. Usually when I see this code come back to the shop I clear it and tell the customer to come back if it comes back on and they'll need a new cat. All that code is saying that the 02 sensor that sits just past the cat is getting signals that the cat is not doing it's job. That is the only purpose of that 02 sensor is to tell the computer if the cat is doing it's job.

So to make it short, just clear the code and see what happens.

 

Wen I purchased my 5th gen used, the SES light was on. Coil pack for cyl #2 was changed for misfire P0302 code. 50 miles after ecu reset, light came back on for o2 sensor high voltage P0138 code and P0430 code. The used car dealer changed all 4 o2 sensors at no charge to me. 155 miles later the light came back for the P0430. Since my emissions was already done, I left it and and instead of paying for the 1 precat, I took the route of post #7 for cheaper & did my own install.

 

bank 1 is the rear (firewall side) and bank 2 is front (radiator side) number one cylinder is always bank 1

fire wall Bank 1
1 3 5
2 4 6
radiator Bank 2

* number 5 on vq35's tends to leak oil into the resevoir due to cheap plastic gaskets.

 

i cleared the SES and it came back.
Two weeks ago i replaced all 6 coils and spark plugs could it had anything to do with it?

 

Ride,

You'll need to spend a little cash to determine the problem. First thing you could do is call Dave Burnette at South Point Nissan (1-8888-254-6060) with your VIN# to see if your car is one that needs the ECU update for this problem. If it's not that then you probably should get the diagnostics performed ($85 for me) on your o2 sensors to insure they are functioning properly. Finally, if that's not it then I'm thinking you'll need the cat. Again, get it from Dave B. (best price) and find somone to put it in. It only took the shop an hour to install mine, but the bolts may be rusted and require additional work to get the old one off. Dave B. told me the cat has been replaced for this problem most of the time.

 

all right man thanks

 

I had my vin checked i dont need the ECu reflash i need the CAt, but i still dont know if the problem is the O2. I spoke with a friend that works in nissan he checked my vin, problably i will take it to him on monday.

 

Same thing happened to me two weeks ago. Got the code cleared and it came back on. I brought it to Meineke and they said that they couldn't replace the cat because it was a dealer-specific part (the one located near the engine as opposed to the rear). So I made an appointment with the dealership for an estimate. A day later, I had a flat tire and got it fixed at Costco. When I got the car back, the light mysteriously turned off. I'm wondering if it was just a coincidence or if Costco turned it off for me? So far the CEL hasn't turned back on and the car works great (no rotten egg smell either).

Also, do you think the type of gas would have contributed to the problem? A couple of weeks back, every station, including the Exxon I always go to, ran out of gas in my area. So I was forced to go to this shady noname place to get premium gas.

 

The probability of the code coming back again is quite high!!!

 

There are plenty of people selling front pre-cats in the 5th Gen Classifieds for cheap. I'd just get one of those and replace it. If you want an even cheaper option which is also much easier, get an O2 simulator.

 

[QUOTE=whitemax99gle]Same thing happened to me two weeks ago. Got the code cleared and it came back on. So I made an appointment with the dealership for an estimate. A day later, I had a flat tire and got it fixed at Costco. When I got the car back, the light mysteriously turned off. I'm wondering if it was just a coincidence or if Costco turned it off for me? So far the CEL hasn't turned back on and the car works great (no rotten egg smell either).

When I had that code, I cleared it more than once. Each time it came back on, I would reset my trip odometer and note the mileage. The miles varied greatly before it came back. When I had a bad o2 sensor, it came back on after exactly 55 miles. If it is the cat the miles should vary as the efficiency dwindles

 

How would you know that its your cat acting up?

 

i dont know thats the thing is either your cat or your o2.

 

I dont know if is the pre-cat or the cat i dont understand that.
Anyone could explain that?

 

Pre-cat is a newborn kitten. Cat is a fully grown member of the feline family.

 

great so the cat is like a tiger or something

 

If is the cat will replacing it with a high flow cat be a better option rather than the OEM because the OEM is expensive i was quoted like 600 just for the cat. I saw some high flow cats for like 200. something online.
So if anyone here knows let me know.
Replacing the cat with a High flow cat would give a SES light?

 

No it won't give a light, just make sure there are no leaks. Unfortunately, high flow cats are only an option for the larger main cat near the middle of the car. I don't believe there are any high flows for the pre-cats. P0430/20 codes are for pre-cats

 

People need to understand this and stop suggesting replacing the main cat when the codes are for the pre-cats.

 

OMG are you an idiot. Please STOP posting forever.

 

thanks puppetmaster you cleared that one out, now putting a y pipe doesnt take out the pre cat does it?

 

For CALI spec 00-01 Maximas, an aftermarket y-pipe will replace ONE pre-cat (rear bank). The front pre-cat is between the front exhaust manifold and the y-pipe and is not removed.

For FED spec cars, the pre-cat(s) are in the y-pipe, so an aftermarket y-pipe on a FED spec replaces the pre-cat(s).

 

 

Ok, please explain this..... per Puppets illistration, how could the o2 sensor decipher between the precats and the main cat(on the Fed)? There is no sensor in between to "smell" the gasses after the precats. there is only one four wire o2 sensor downstream of all the cats period. the two o2s in the banks are in front and can't readout the precats.

I have a 00' with all brand new o2s, a warpspeed y, and a magnaflow high flow cat. And I have this code.
please help me understand this, Brent

 

thanks guys now its clear with the Y pipe but how about Headers will the take out the pre cats on a CA emission?
Since i have to spend like 600 i should just put a little more and get headers?

 

pull that VQ35 camshaft out of your a$$ and chill...

 

Remember, the engine needs the two o2 sensors to regulate air/fuel ratios as the exhaust comes from each bank. There are 2 primary ones that handle that task. They don't care about what the cats are doing. Any o2's after any cats sole task is to measure the cats efficiency, whether it's a pre-cat or a main cat. To reach emissions standards, Cali cars must have smaller cats that react quicker than the main cat to reduce emissions on startup. They have an o2 to monitor each one. Fed spec standards arent as high so they can get away with just making sure the main cat is working. Why a Cali spec's main cat is not monitored, I'm not sure. Anybody, please correct me if I'm wrong.

 

If you purchase headers, it will only remove the pre cat on the manifold near the radiator, also known as bank 2, which only Cali cars have. There is no precat on the manifold near the firewall, known as bank 1, on either Fed or Cali specs. On both specs, the bank 1 pre-cat is on the y-pipe. Purchasing an aftermarket y-pipe will eliminate that one only. Buy headers also and you will have none.