i've been getting my car passed under the table for years now
but i've been wondering if any of you passed using a o2 defouler?

that's the only code i have on there so i just throw a defouler on there to take care of that.

from my understanding 2000 and up they just use the obd2 to check for ready codes and no actual emission testing.
just wondering if the tech specifically looks for that on an obd2 smog.

 

My car is a 2000 and I live in California. No defouler - I don't think I would pass, more below.
My last inspection took place in November 2019. It consisted of the following steps:

• Checking that there are no outstanding codes, AND ensuring that all ODBC tests are "completed". The test station makes the test by connecting a special ODBC connector and the results go directly to Sacramento (this makes any meddling by the tester impossible). If I remember correctly, this step was done with the engine running.
• A fairly detailed inspection of the engine bay. The tech used a "mirror on a stick", and he poked around for about 4-5 minutes.
• A similar inspection of the rear end. Again, he used the "mirror on a stick" to inspect the vehicle from underneath, and the passenger side in particular (presumably, he was checking for defoulers but in strange places).
• There was one more item - I no longer remember what it was.

I was now forced to replace my pre-cats twice (in 2019 and 2015). I am praying for not having to do that again in 2021 when my next inspection comes up.
Apart from this smog/pre-cat hassle, my car - with 165K on the odometer - runs like a fine watch.

 

I pass in NYC with defoulers. They do an ODB2 check and a **** poor visual check. The guy walks past my wheels and briefly flashes a light at my brakes through the wheels to inspect my brakes.

With the defoulers, I don't have and codes from my gutted precats is what I am getting at. Defoulers are small and would blend in if they aren't shiny and new.

 

hmm. i guess the trick is to look for a smog place that does a **** job at checking for defoulers.
or just pay to get it illegally smogged again. which is getting more expensive.

i wonder if i can get like a pre - check somehow so they can check without making it official
so if they find the defouler i can just go "ohh, i don't know anything about that" and move on.

 

i pass in the north east with full inspections and emissions using an O2 sim on gutted cats

 

^ link to o2 sim pls?

 

mine is officially discontinued, bought it in 2015 , here are two links i have tho that may be good, i am pretty sure first one is one i found on the org.
first link
second link

 

its kinda pricey but ! they are what they are! i

 

I bought my presently installed one when I went to Cattman Headers over 10 years ago...Do you need a dual or a single?

 

In Cali, since they dyno emissions test the car during a legit smog test, defoulers won't work. Unless your engine/cats are functioning properly, at which point it would just be easier to replace the rear O2s.

 

from what i'm reading 2000 and up they just put it on an obd reader and check for ready status and codes.
it's a single defouler cats and pre cats are still perfectly in shape other then they don't work anymore.

or maybe they do? it's just the code saying they don't but maybe pass. idk what it measure exactly.

 

For the record, there is no need for “dual” O2 sims. You can use a single sim to simulate both sensors. All it is, is an extra wire. You can also build your own sim if you are handy with a soldering iron.

If theyre poking around the engine bay though, there is a risk they will find the sim, and thats a pretty massive fine if it is found. You could alternatively use RomRaider to reflash the ECU, there is a “cheat” mode that makes it so that all monitors are forced into ready position. You just have to flash it back once thats done or else youll get a code for a bad ECU or something or other, its something you do right before the test. No way they could spot that unless they happen to be looking at the absence of long term fuel trims but that would never, ever happen, and even then there is other logical, non illegal reasons why they wouldnt be present.

If you are getting actual smog tested though, youre SOL as far as i know. I dont see a way of fooling the sniffer.

Edit: None of the techs give a flying fck about your car or whether or not it is illegal. What they do care about is if youre a narc pulling a string operation on them, which is why most shops will absolutely refuse to do something under the table for a stranger. If they get caught, they lose their business. Not worth the risk for them.

 

2000 and up and they don't stick a sniffer in the tail pipe, but it does run on the dyno while their machine is connected to the OBDII port getting readings.

 

I could have sworn they did a sniffer test on my 03 M5 last year when I bought it but I can't find the print out. (It's registered there)

 

That could be the case at some shops, but the last 2 smogs I've had consisted only of an OBD II test and visual inspection. No dyno. My guess is that defoulers would be spotted during the inspection.