Best way to run catted section 1 for CA smog ?

[bavarian3]

Trying to get some clarity around installing right components for my catted section 1 in California.


Goal: Run a catted section 1 in a way that will pass California smog(visual disregarded), and not throw intermittent cat efficiency codes.


What I'm pondering for options:

Option 1: Install post-cat o2 sensors, have someone tune down sensitivity. However, I read a post stating "as of monday the BAR in california will begin checking for modified ecu code."

Option 2: Install post-cat o2 sensors, code them out, then code them back in for smog?

Option 3: ?

Not sure if EGT sensor matters in any of these cases.


Any and all input is appreciated here.

[oceansize]

Option 1: Install post-cat o2 sensors, have someone tune down sensitivity. However, I read a post stating "as of monday the BAR in california will begin checking for modified ecu code."

They have supposedly been doing this since 2021 but I haven't heard of anyone from this forum getting flagged for an aftermarket tune. Perhaps they don't have the data for our cars to perform the checksum part of the validation. Or maybe everyone here is flashing their car back to stock.

Anyone from CA have any info on this? I'm curious even though I don't live there.

[Tbonem3]

Checksum issue is for 08+ I think. Haven't seen one issue with e46.

[bavarian3]

They have supposedly been doing this since 2021 but I haven't heard of anyone from this forum getting flagged for an aftermarket tune. Perhaps they don't have the data for our cars to perform the checksum part of the validation. Or maybe everyone here is flashing their car back to stock.

Anyone from CA have any info on this? I'm curious even though I don't live there.

SO I got info from a birdie that what you mention is mostly correct. It looks like they don't have the data from BMW as it's only recently the manufacturers provide it, but may have crowdsource data from collective smog tests. Either way it doesn't seem to cause any flags when it comes down to it.

[bavarian3]

Checksum issue is for 08+ I think. Haven't seen one issue with e46.

So this still leaves the question on the best way to handle whether to use post-cat o2's, EGT, coded down or not.

[9kracing]

I'm not sure I believe this rumor about them checking for modified ECUs. I just had to smog my Focus RS a couple weeks ago, and it's got a tune that is NOT 50 state legal, and the guys didn't mention anything. In fact, I forgot to unplug my Cobb Accessport from the OBD port, and the smog guy just thought it was to monitor engine vitals. Passed no problem.

[oceansize]

I'm not sure I believe this rumor about them checking for modified ECUs. I just had to smog my Focus RS a couple weeks ago, and it's got a tune that is NOT 50 state legal, and the guys didn't mention anything. In fact, I forgot to unplug my Cobb Accessport from the OBD port, and the smog guy just thought it was to monitor engine vitals. Passed no problem.

That's a good data point because they should have data on a Focus RS (although they had a fairly limited run). I've always wondered if they were actually able to implement this like they said they would.

Illegal modifications to a vehicle’s emission controls can dramatically impact the amount of pollution the vehicle generates. This is true not only for modifications to physical components (e.g., air intake, catalytic convertor) but also for modifications to the software controlling the vehicle’s engine controller (e.g., computer). Programming modifications can be detected using the vehicle’s calibration identification (Cal ID) and calibration verification number (CVN), which together uniquely identify the software program installed on the computer. The Cal ID is the name of the program assigned by the vehicle manufacturer. The CVN is a unique numeric code calculated based upon the computer program. Whenever a computer’s program is modified, a new CVN will automatically be generated that will differ from the one originally associated with the Cal ID.

Over the past year, the Bureau of Automotive Repair (BAR) has been extensively studying Cal ID and CVN and working with the California Air Resources Board (ARB), vehicle manufacturers, Smog Check industry representatives, and BAR Advisory Group members to gather input and develop an implementation plan. In accordance with California Code of Regulations, title 16, section 3340.42.2(c)(8), beginning July 2020, BAR will implement Cal ID and CVN checks for most model-year 2000 and newer vehicles as part of the On-Board Diagnostic Smog Check inspection failure criteria. Owners of vehicles identified with unapproved programming modifications will need to restore the computer to either stock or ARB-approved software in order to pass a Smog Check inspection.

[simonnim]

But, I wonder they they're checking for? If it just matches what they have to the database? Or like based on vin. Manual swapped technically have a 'tune' that doesn't match. I think my ews is coded out too lol.

[bavarian3]

But, I wonder they they're checking for? If it just matches what they have to the database? Or like based on vin. Manual swapped technically have a 'tune' that doesn't match. I think my ews is coded out too lol.

with the info I posted above this was also highlighted, that 6mt swapped examples would have run into the same issue

[simonnim]

So in other words - tune away? drill out your cats? add extra spacers to your o2 sensors so that it'll pass?

[oceansize]

So in other words - tune away? drill out your cats? add extra spacers to your o2 sensors so that it'll pass?

The CVN is a value provided by the manufacturers. Every time your tuner or any third party software changes your cars tune the CVN changes. This is unavoidable. If they are checking then they can simply compare your CVN to the list provided by manufacturers.

However, like I said nobody on this forum has ever indicated they are following through with that check. I don’t know how sophisticated their inspection setups are but this would imply that every inspection shops equipment has a way to communicate back to the mother ship to get the latest CVNs for new cars. Seems unlikely to me.

[bavarian3]

The CVN is a value provided by the manufacturers. Every time your tuner or any third party software changes your cars tune the CVN changes. This is unavoidable. If they are checking then they can simply compare your CVN to the list provided by manufacturers.

However, like I said nobody on this forum has ever indicated they are following through with that check. I don’t know how sophisticated their inspection setups are but this would imply that every inspection shops equipment has a way to communicate back to the mother ship to get the latest CVNs for new cars. Seems unlikely to me.

based on this then, my car should've failed(I passed without a hint of a fuss fwiw) smog considering I have a shark injector.

[oceansize]

based on this then, my car should've failed(I passed without a hint of a fuss fwiw) smog considering I have a shark injector.

Yes it would have failed had they checked your CVN so it appears shops are still not checking our cars and hopefully never will. I've seen threads on other forums (Corvettes) where owners were flagged for their modified tunes (or at least the forum members claimed).

[Tbonem3]

So this still leaves the question on the best way to handle whether to use post-cat o2's, EGT, coded down or not.

Check my journal. Basically a euro car setup with working post cat 02s. Egt isn't needed or checked by CA smog so do whatever you want (I don't bother).

[zzyzx85]

I'm running Euro catted section 1 and it passes smog. All O2 sensors are plugged in. The harness was extended so they could reach.