Codes P0420 & P0430. V8 catalytic converter issues

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Ilya
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Correct. What I was told was that if it doesn't rattle, that means the valve inside or what not is stuck and therefore it's not doing it's job. Rattle = good.


Larz
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According to my research, a CAT will rattle ONLY when part of the inner substrate has come loose, which is a sign that the CAT is breaking down and will eventually fail or clog. Nobody can say with any accuracy how long it takes to go from a rattle to a clog. I reckon as long as the substrate pieces remain on the bottom of the CAT, it may never actually cause a clog. It's the fickle finger of fate pointing at you and sayin " I've got my eye on that, you know". You may be losing performance if the pieces hinder the flow of exhaust and it may or may not pass an inspection at renewal time. Put another way" That money you have been saving for a rainy day? ... The rattle means there is a storm on the horizon.
As for a rattle after a new CAT is impossible. It's likely NOT the CAT itself, but the adjacent / attached heat shield that was damaged during the install. When mine were replaced at the dealer, they told me one of my shields broke. They told me it won't fall off and the CAT is not damaged, but the loose shield will likely rattle so they gave me the option of waiting 4 days for them to get another new CAT, or have them re-weld the shield back into place and it will be covered like the CATs with free replacement if it ever fails.

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Ilya
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Larz, we're talking about PCV valves now (as far as rattle) :p.

Larz
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Maybe you can just blow the broken pieces of the CATs out the exhaust .. how hard could that be ???? ... Have a squinz at these rocket scientists trying to avoid the cost of new CATs. These guys are a prime example of gear heads who don't know nearly as much as they 'think' they do LOL. AND just when you think a car fire is the worst that could happen? Watch what happens next !

Yoda's Master
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I think it can be saved. Some new wheels and a paint job,...good as new!

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armybrat
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Larz wrote:
Mon Sep 30, 2019 5:19 pm
Chances are, regardless of which fuel station you purchase your fuel, that fuel probably came from Shell Oil (technically Royal Dutch Shell) - the largest gasoline supplier in the US. The difference from one brand to another (at the actual pump) are the additives and detergents used by Exxon Mobil Vs BP Vs Chevron, etc. Shell stations claim to have the best additives and they charge significantly higher prices than competitors. I have tried a few tanks of Shell with no noticeable difference in mpg or performance so I never went back. We must have standards though - I won't purchase fuel at any convenience store or any shabby looking station because I wonder if the underground tanks have rusty water and contaminants in them. If the station or store is unkempt, I assume their tanks are equally uncared for. I always by 93 octane (91 is not available here) and usually from the same Mobil station each time. I will never buy anything from BP - not after the destruction, the outright lies, and lack of humanity they showed and continue to show in the deepwater horizon disaster - not even if their prices were half what I currently pay.
I also switched to the Shell 93 V Power, been running it since 109075 miles. I did get a P0420 at 110159 miles and another one at 110300. Last time I added Cataclean was at 108138, so I added another one this time at 110303. Like you, I did not notice any mileage or performance gains. My main reason for trying this gas is to see if the additives in this brand makes a difference in cat performance. I was stoked when I made it 1084 miles the first time, but was major disappointed when it popped 141 miles later. I am hoping that continued use will make a difference but I getting more convinced that the life expectancy is reaching, or has reached the end, and it's time to bite the bullet and have them replaced. I will try this gas a while longer and see if the second DTC was a fluke/anomaly...meanwhile, I did find the best prices on the infinitipartsdealer website:
Image

I will also see about sourcing the labor, since I will have the parts in hand. I will talk to my dealer again to lock in a labor cost to do both, then maybe check around some other shops as well.

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Ilya
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I'm getting the same results Army since switching from Stewarts (local chain) 91 Non-Eth to Sunoco 93 (E10). Sometimes I'll go 500 miles without a CEL, sometimes I'll go 100. So I think like you it's just a crap shoot and most likely our cats are SOL. My hope is that I can get one more NYS inspection done next summer and when I get my bonus next November, fork over the $2,500-3,000 and just have them be replaced and continue enjoying my car for the next few years. Other than 2 or 3 little rust spots on the roof before the sunroof (from rocks I'm assuming) and this P0420 code, my car has zero other issues and I'll continue to drive it till it's not feasible to do so.

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armybrat
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Ilya wrote:
Sun Nov 17, 2019 5:16 pm
I'm getting the same results Army since switching from Stewarts (local chain) 91 Non-Eth to Sunoco 93 (E10). Sometimes I'll go 500 miles without a CEL, sometimes I'll go 100. So I think like you it's just a crap shoot and most likely our cats are SOL. My hope is that I can get one more NYS inspection done next summer and when I get my bonus next November, fork over the $2,500-3,000 and just have them be replaced and continue enjoying my car for the next few years. Other than 2 or 3 little rust spots on the roof before the sunroof (from rocks I'm assuming) and this P0420 code, my car has zero other issues and I'll continue to drive it till it's not feasible to do so.
Just an update, not sure if it's the colder weather but the code is popping up more frequently since my last post at 110300:

110975 - started using Shell V Power
110159
110300 - added Cataclean
110664
110995
111105 - reflash tune at 111123
111265 - CEL just came on yesterday on the way home from work

Also not sure that switching from BP to Shell made a difference in this case. Since I've been using Shell, I've had 6 DTC's in 2190 miles. The timing with the colder weather now prevailing could have something to do with it. The manifolds are simply reaching the end of their usefulness. I am going to switch to Mobil for a while just for kicks; they opened a new station right on the way to work, on the right side of the road. Easy access, no traffic lights just turn right in, fill up, and right back on the highway. I filled up there a few times before trying the Shell. The Shell station near my house is a PITA to get in and out of, so I won't miss that.

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Ilya
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Yeah, I've resigned myself to the fact that it's game over for mine so I just clear the light whenever I feel like it so it doesn't burn my retinas, but otherwise I'll be likely getting them replaced next fall/early winter.

Yoda's Master
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I wish someone would just make some down pipes

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CRV_33
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Found this on my Google search from Magnaflow’s website. Looks like they’re making their own version of a catalytic converter:


https://www.magnaflow.com/collections/2 ... converters

DRM56
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If Magnaflow can come thru with these new manifolds, I will be down to buy them versus paying Infiniti almost $2,200 for one. Pretty crappy design so hopefully these will be better than OEM specs

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I was slightly more fortunate with my M35 because the engine did not have to be raised to replace them. I was able to buy the OEM CATs direct from infinitipartsonline for less than half the dealer price for the same part numbers. I decide NOT to use any aftermarket brands because I read horror stories where many name brand aftermarket CATs would only last 2 years, or would fail emissions testing in the states where testing is required.
I saved an absolute TON of money based on what the dealer was going to do to me. But I still feel violated, LOL. Here is the post I made last year:

Post by Larz » 23 Apr 2018, 18:37

Recently, I had to have 02 sensors replaced and about 2 weeks later, same issue. The techs determined that my cats are causing low oxygen levels. Remedy is to replace both cats. Unfortunately, warranty does not cover exhaust systems. I tried to riggle with them stating it's not exhaust but a federally mandated EPA requirement. I thought that might let it slip by, but they weren't having any of that so I have to pay. The dealer estimate was $1335 for left and $925 for right + $1200 "shop supplies / parts" and labor = $3460 !!!

I went to Infiniti parts online and paid $835 left and $693 right with $71 shipping. They come with new gaskets, bolts, etc so no parts needed. Installation is still $1200 for an estimated total of $2728. BUT ..., when I ship the old units back for a core exchange, I will get $284 back (less shipping back to Inifniti) which lowers the total bill to $2444.
I saved $1,000 by NOT getting the parts through the dealer and I still get the same warranty through Infiniti because its OEM and the dealer installed them. Again, what dealers call a mark-up, is actually ROBBERY plain and simple!
Now I see why some peeps opt to delete the cats or use a cheaper off-brand unit.

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CRV_33
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Keep our fingers crossed! Someone on Facebook posted that PPE Engineering is using his M56 to build a prototype long tube headers. Hopefully more good news down the road!

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ken in az
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ppe-engineering-headers-and-full-exhaust-t626437.html That would be me - haha :dblthumb:
CRV_33 wrote:
Sat May 09, 2020 8:09 pm
Keep our fingers crossed! Someone on Facebook posted that PPE Engineering is using his M56 to build a prototype long tube headers. Hopefully more good news down the road!

Rameek7daGod
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I just made an order for the driver side manifold w/cat, gasket exhaust, manifold gasket, oxygen sensor for 1200. Mine is bank 1.
This site i realized if you change the zip code you'll get different deals and prices. I've been ordering from this infiniti shop lately. My NYC offers were $300 to $400 more. Plus they had a sale. Great experience with them so far.
https://www.infinitiofwestchesterparts.com/cart.aspx

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Have you tried here https://www.infinitipartsdeal.com/parts ... 02+A,14002

My headers from PPE are sweet btw

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ken in az wrote:
Wed Jul 08, 2020 8:23 pm
Have you tried here https://www.infinitipartsdeal.com/parts ... 02+A,14002

My headers from PPE are sweet btw
I was nervous to use them even though they have good pricing. If I needed something unofficial parts I'd possibly use them. If people here have never had issues with that site and they're offical I'd consider it.

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Rameek7daGod wrote:
Thu Jul 09, 2020 4:18 am
ken in az wrote:
Wed Jul 08, 2020 8:23 pm
Have you tried here https://www.infinitipartsdeal.com/parts ... 02+A,14002

My headers from PPE are sweet btw
I was nervous to use them even though they have good pricing. If I needed something unofficial parts I'd possibly use them. If people here have never had issues with that site and they're offical I'd consider it.
Their parts are genuine OEM. I don't fully understand the business model, but when I've made large orders, it seems like they fulfill it by sourcing from different dealerships.
Their website is impeccable, and their prices are most times the lowest for most items.
In my experience their downfall is their customer service. I avoid using them if I am buying anything that needs to adhere to a timeline.

Rameek7daGod
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EdBwoy wrote:
Thu Jul 09, 2020 8:24 am
Rameek7daGod wrote:
Thu Jul 09, 2020 4:18 am


I was nervous to use them even though they have good pricing. If I needed something unofficial parts I'd possibly use them. If people here have never had issues with that site and they're offical I'd consider it.
Their parts are genuine OEM. I don't fully understand the business model, but when I've made large orders, it seems like they fulfill it by sourcing from different dealerships.
Their website is impeccable, and their prices are most times the lowest for most items.
In my experience their downfall is their customer service. I avoid using them if I am buying anything that needs to adhere to a timeline.
I kinda seen that online. Luckily I found the Infiniti place with slightly more expensive oem products but their customer service is impeccable. Plus it's official

Rameek7daGod
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Ok so I just had my driver side manifold and catalytic converter installed. It came with the 02 sensor. I'm going to put 50 miles soon to test it out. I'm getting my undercarriage cleaned and coated if this clears the codes.

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Ilya
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After speaking to some other mods/admins on this site, it was recommended I try this cheap fix ($12 bucks) before proceeding:

2 x https://www.amazon.com/gp/product/B000C ... UTF8&psc=1

Then follow this guide:

https://www.youtube.com/watch?v=kzm52m0AWSQ

Lets see if this works. I'll be doing this in the next week or two.

Yoda's Master
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Ilya wrote:
Mon Jul 27, 2020 5:54 am
After speaking to some other mods/admins on this site, it was recommended I try this cheap fix ($12 bucks) before proceeding:

2 x https://www.amazon.com/gp/product/B000C ... UTF8&psc=1

Then follow this guide:

https://www.youtube.com/watch?v=kzm52m0AWSQ

Lets see if this works. I'll be doing this in the next week or two.
If you recall, i suggested this fix on page 4
codes-p0420-p0430-v8-catalytic-converte ... l#p6796396

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Ilya
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Yoda's Master wrote:
Tue Jul 28, 2020 9:19 pm
Ilya wrote:
Mon Jul 27, 2020 5:54 am
After speaking to some other mods/admins on this site, it was recommended I try this cheap fix ($12 bucks) before proceeding:

2 x https://www.amazon.com/gp/product/B000C ... UTF8&psc=1

Then follow this guide:

https://www.youtube.com/watch?v=kzm52m0AWSQ

Lets see if this works. I'll be doing this in the next week or two.
If you recall, i suggested this fix on page 4
codes-p0420-p0430-v8-catalytic-converte ... l#p6796396
:facepalm: How did I miss this? Thanks Yoda!

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Ilya
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IT WORKED!

howto-p0420-p0430-workaround-fix-m37-m5 ... 27166.html

But I have a PA200 code now on bank 1 (driver side). Does that mean that I just need to replace that sensor?

Rameek7daGod
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I apologize didn't mean to make my post in your other thread. Please delete.
Ilya wrote:
Fri Aug 21, 2020 7:45 am
Rameek7daGod wrote:
Thu Aug 20, 2020 8:44 pm
I had the P0420 Bank 1 issue for a few years.

I purchased this came with a sensor. I bought a sensor in addition but my mechanic saw it had one so I returned it.

https://www.infinitiofwestchesterparts. ... 1CX0A.html

https://www.infinitiofwestchesterparts. ... tedProduct

Gasket for the flange.

I only bought 3 parts for this project.

I didn't have to replace anything else. Problem resolved. They did have to cut the original manifold. I did not stay to see the work in total but it was in the shop for a day.

I sent the cut in half manifold to Infiniti of Westchester. I just got the email today Infiniti accepted it and I'm getting my core charge refunded.

I did get a hefty discount on the work because they're a close friend to a friend.

I did notice based on location the parts price changes. But I've bought all of my official parts from this location great customer service! They answered all questions promptly.
Yes, we know that is the 'official' fix, but most of us don't have or don't want to spend the load of money it takes to fix this 'officially'. If I can spend $250 to fix a $2,500-3,000 issue, I'll do it all day and twice on Sunday.

Infiniti's design when it comes to some part of this car is absolutely horrible. Who's bright idea was it to put the cats in the manifold? My M35x wasn't like that to my knowledge and neither were my two Nissan Maxima's.
I explored the option you did. I actually bought everything to do it. I think you're right as far as a fix and from what I've seen no one has posted on YouTube of any longterm failures or issues.

I realized it's not at expensive as I thought just saying if you only have bank 1 issue. Manifold w/cat, manifold gasket, flange gasket O2 sensor comes with it. They didn't drop my engine or lift it.

I definitely didn't spend 1200 for these parts either my error. I forgot I bought some other stuff.


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