No idea. The supercharged and turbo guys would probably benefit, but not sure to what extent. Both my cats are still in place, but I still got the P0420 code.

Any modification of the emissions system on any car from original spec is illegal under Federal law--inspection or not. Obviously, your risk of getting caught is near zero-unless you sell it and the next owner gets popped and it comes back on you--also pretty unlikely if you are careful about who you sell to.

I don't know all the state laws, but you are altering the approved emissions system, so you could be breaking laws in some states, or there could be some federal laws applying too, I'm not totally sure. I know in Cali these are illegal for sure. Some of Cali's CARB laws are becoming federal laws, or soon will be, so there may be something on the books everywhere outlawing simulators for on road use.

Most places don't do a sniffer test on vehicle 96 and newer because of the ODB system. If they let you get away with it, then fine, but just know that it is legally dubious unless you KNOW your state allows it. I mean that is why URD has the disclaimer "Sensor Simulators are not CARB Approved, and are never to be used on Pollution Controlled Vehicles or on Public Highways"

Uh, I don't think "most definitely" means what you think it means. Saying most definitely kind of suggests that you have definitive proof that this is all a URD simulator is. If that's the case, then please post some pictures and actual explanation, or at least some other explanation. Have you electrically modeled a URD simulator?

I was just trying to play devil's advocate here. I'm sure URD's simulator is more that just the cheapo cap and resistor the OP used, so just don't bash it until you have some better evidence that they are marking it up 20x of cost.

Ah, you beat me to it. I figured there was some stupid federal law on the books regarding this.

I think the only way you will get caught is by the state you are in enforcing the federal law, so in states that don't have inspections, I highly doubt you'd get caught. In cali, you probably will from the description of the CARB checks.

As far as deleting the cats goes, that is alot more obvious for even the most basic inspections, and you actually are making the emissions alot worse in that case. I am against costly regulation that requires 96% efficiency and bends you over the table for new platinum cats if you have 95.5% efficiency, but going to no cat at all really does put more bad crap out into the air, and is not a good solution.

I replaced my rear O2 sensor a couple weekends ago, which meant that I no longer have the mod in place. I did it just to see if both my cats were really bad, or if my rear sensor was just worn out. My CEL popped on not long after, pretty much indicating that my cats are not operating at the efficiency level that the ECU would like. My wife threw away the old O2 sensor with capacitor and resistor still attached thinking that it was junk, so I'll be making another trip to Radio Shack to redo the modification.

Well, you still haven't figured out if your cats are bad, you could still have an exhaust leak. Any of the mods done to stop a P0420 code will mask both an exhaust leak or a bad CAT I think.

Have to given a full inspection of your CATs? It was pretty easy for me to lay underneath with the engine running and move my hand around the flange joints to see if I could feel a warm air leak. Pretty easy to find. Do that before you make any decisions on how to solve this.

Seems like a moot point when I can just put the resistor and capacitor back to make the P0420 go away.

Maybe for you if GA/TN doesn't do inspections and you are willing to risk getting caught, but for anyone reading this thread from Cali or other states, it's not a moot point at all. No post here is really just for the OP, others read them too.

Plus, alot of people actually want to fix their vehicle, not spoof it. That's not criticism of your decision to spoof it, it's just what alot of people here prefer.

TN has inspections in certain cities (just took my wife's 2012 Civic through a couple months ago. GA does also. Last time I went through inspection they checked to see if my vehicle had a catalytic converter present, checked with OBD2 reader to make sure no codes were found, and then hooked something up to my gas tank in place of the gas cap to check what I can only assume is the EVAP stuff. I imagine most other states do something similar.




BS. Judging by how many threads ask about how to fix the P0420 code without dropping a small fortune on new cats, we both know that's a false statement.

Yeah, so they may not notice the extra bit of "fat" on your O2 sensor wrapped in electrical tape, but if the inspector is alert, they easily could notice it. Here in MA they don't typically get under and look at it, they just check the OBD2 port (though I try to go to the laziest inspectors so that they don't get under and check, because I think they are supposed to).

Ok, it's not BS, read those threads again. Most of those guys not wanting to drop a fortune on their cats are not opposed to replacing the CAT with aftermarket ones for under $300 for the set ($150 for 49 state). In the last couple years I have seen a pretty good number of guys use aftermarket CAT's and post up here that it took care of their P0420 code. When I first got my 4runner back in 09, I couldn't find any records of people positively saying "XXXX brand aftermarket cats took care of my P0420 code", but there were a couple people that explained that the OBD2 system standards for the emissions were pretty high, and aftermarket (non-platinum) CAT's may not be able to achieve sufficient efficiency to turn off the OBD2 code. There wasn't a clear solution other than "illegal for on-road use" simulators or forking over for OEM cats that was guaranteed to solve the P0420 problem (or had a good track record).

Of all the threads about that I have seen, the majority of them seem to be deciding to go with aftermarket CAT's, not the URD sim, or the $5 sim that has been out on the internet for years. And 1 or 2 I can think of went to a muffler shop and got an exhaust leak fixed, which was my point. I don't know how you can call my comment BS when it is demonstrably true. Yeah $5 is cheap, but I haven't seen anyone choose that route in a very long time.

I hope you aren't interpreting my posts as criticism of your method. That method has been around for years, and seems to work pretty well, no dissing it as a workaround. The URD sim offers something a bit more, if no more than an (expensive) environmentally protected package and plug and play simplicity. I feel confident in saying that the vast majority of the old timers here would recommend figuring out the actual problem before slapping on a band-aid if for no other reason than to know what you're dealing with.

Count me in! I'll play this game for $10. As for the cat, just keep the damn thing. This is not a performance engine, it's built for economy. Sorry to burst anyones bubble but it's not like you see the amazing 3.4 being swapped into anything going down a drag strip or anywhere near any track. That would be the 2JZGTE.

Yeah, I'm with you. I kept it as long as I could, snuck my way through a couple inspections, then just stopped getting inspected for 4 years. Then all of a sudden I got 2 tickets for it in 2 days and had to get it to pass inspection.

Found a new winter project, goodbye kitty!

With regard to the visual inspection in TN, it's a complete joke. The tech sticks a mirror under the car but I don't even think they know what they are looking for. I have an 08 civic that has the catalytic converter bolted directly to the cylinder head in the engine bay, there is not a cat anywhere underneath the car nor can the cat even be seen from under the car. Yet they still use the mirror and give me a visual pass every time. They could not possibly care any less about the job they are doing. If you pass the obd test and the gas cap pressure test, then you pass. Doesn't matter if you go in there and stink up the entire testing center with a hollowed out cat and 02 sim, you pass (or so Ive been told).

Someone correct me if im wrong here.

Ive been told that on newer engines that were designed to be used with catalytic converters in the system, performance and mileage can actually suffer from complete removal. Something to do with losing too much back pressure. Not to say you need the super high doller oem cats, just some good quality aftermarkets.

Dont get me wrong, im not against you or anyone else taking them off. I probably would too if you could gaurantee me better performance and fuel economy. I think the old days of the super restrictive cats are long gone.