P0420 code - SOS downpipes & Fabspeed Cat Back exhaust

Here's a free and easy way to determine if your car has a JB4! Download a bluetooth scanner on your phone, turn on the ignition, and look for "JB4" in the list of nearby devices. Mine shows as "JB4 R36" which I guess means revision 3.6. The free iOS app I used is called Wunderfind.

I didn't even realize my car had it. The previous owner was really into performance, but I figured the JB4 would have been removed and sold before trade-in. Thanks to @drmanny3 for the tip about JB4 being impractical to remove. Now I can fork out $28 for the JB4 Mobile app with peace-of-mind that the car actually has the box installed :)
OK I've used this app to scan for JB4... Nothing shows up.
 
The process of checking for the Bluetooth signal from the JB4 sounds like a good idea. However as you found out the meth system was turned off, perhaps the same for the JB4? The best thing is to pull the engine covers (pretty easy to do) and look for the unit based upon the install video from SOS. On the SOS website, Chris indicates that the Meth injection can be purchased separately especially if the car has been driven really hard and is not running smoothly or something to that effect. However the best reason was to marry the Meth Injection with the JB4 unit. It probably takes a couple of hours to install The JB4, so I suspect it would take time to remove. Also, if removing the JB4, why not remove the Meth Injection system.

On another note, have you attempted to identify previous ownership? A friendly service rep can pull ownership of the car. That way you might be able to determine what has happened.

Is the Meth Injection system serialized? If so perhaps SOS has some history on whether it was purchased separately or with the JB4.
 
The process of checking for the Bluetooth signal from the JB4 sounds like a good idea. However as you found out the meth system was turned off, perhaps the same for the JB4? The best thing is to pull the engine covers (pretty easy to do) and look for the unit based upon the install video from SOS. On the SOS website, Chris indicates that the Meth injection can be purchased separately especially if the car has been driven really hard and is not running smoothly or something to that effect. However the best reason was to marry the Meth Injection with the JB4 unit. It probably takes a couple of hours to install The JB4, so I suspect it would take time to remove. Also, if removing the JB4, why not remove the Meth Injection system.

On another note, have you attempted to identify previous ownership? A friendly service rep can pull ownership of the car. That way you might be able to determine what has happened.

Is the Meth Injection system serialized? If so perhaps SOS has some history on whether it was purchased separately or with the JB4.
The meth system is an AEM brand. The module looks like the picture below. It is located on the driver side
I unplugged it from the white connector so it's not currently working. Since it's a AEM, I highly doubt it was an SOS system. I could be wrong tho. I will check later on and pull everything out and check. My brother has a mechanic friend and he is saying that it could be that the car had the ECU flashed and since is not detecting the meth system working, it might be th reason is throwing the code. But as far as my understanding is that this car is impossible to flash since no one has had an actual working tune for it. So I've been told... As for the dealer... Well I the 6th owner so... I don't think it will be possible to locate all the owners. Plus I don't think they will be willing to help me at this point. (something happened between me and the dealership a few months back)
 

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Ok, I did not know that AEM sold that for the NC1. AEM only lists the 2005 NSX as the newest NSX that their Meth System is for. The Dealer you purchased from may not be helpful. You can pull some history by pulling the CarFax history. One of the other Acura dealers may be willing to pull service history on the car by blacking out the owners name. I easily got this info on my car. You might also join the Facebook Second Gen NSX Group. Someone there may recognize the car. The Administration there may check the Vin Number and direct you in the right direction?
 
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Ok, I did not know that AEM sold that for the NC1. AEM only lists the 2005 NSX as the newest NSX that their Meth System is for. The Dealer you purchased from may not be helpful. You can pull some history by pulling the CarFax history. One of the other Acura dealers may be willing to pull service history on the car by blacking out the owners name. I easily got this info on my car. You might also join the Facebook Second Gen NSX Group. Someone there may recognize the car. The Administration there may check the Vin Number and direct you in the right direction?
OK ill see what I can do. But what it looks like so far is most likely keep the car for a few years to build equity and then get rid of it. I feel that it might be a ticking bomb at this point. Im going to look into Facebook and see what I can find. Thank you very much for your guys help.
 
I don’t have enough data to say if there will or will not be any issue. The extenders are for us who already have sos converters and have the P0420 and P0430 codes for each bank converter. You may want to reread the thread. Yeyo2021

I was getting ready to install my SOS downpipes, think it would be wise to just install the extenders at the same time?

I just ordered the Racing Dynamics 45's from Uro Tuning. They were about half the price of the Fabspeed ones and my mechanic said to order them. My NSX guru and mechanic just installed his SOS downpipes and is getting the same codes.

Was thinking this was a simple, easy upgrade but I really don't want a check engine light or any drawbacks to this.
 
I was getting ready to install my SOS downpipes, think it would be wise to just install the extenders at the same time?

I just ordered the Racing Dynamics 45's from Uro Tuning. They were about half the price of the Fabspeed ones and my mechanic said to order them. My NSX guru and mechanic just installed his SOS downpipes and is getting the same codes.

Was thinking this was a simple, easy upgrade but I really don't want a check engine light or any drawbacks to this.
Don't know what to tell you anymore... I got rid of that NSX POS of car.... Not only had the p0420 code that never went away no matter what I did... But it also.... All of the sudden gave me the p0011 code out of the blue.... Not sure what was that all about. Honda reliability... A Joke. Spent almost 7k trying to fix the problem but it was useless. A money pit of a car. I cannot imagine once those batteries go out of commission. Be prepare to sell ur kidneys once that happens. In maybe 5 years or sooner those cars are gonna be so problematic that that they are gonna deapreciate worst than a maserati ghibli... I got me an LC500... Awesome car... Reliable as hell and no problems at all. Good luck my dude. Hope u don't end up like me.
 
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