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Diavolo 01-18-2013 03:20 AM

New CA Smog OBDII Info Thread

Update June 2014:
Looks like some places are still doing the sniffer test.
We're able to pass with any tune as long as we have the catalytic converters to clean it up /pass visual.

Let's post info here.
Anyone had to Smog yet?

What do you guys think about OBDII reading as means of Emissions test;
Good thing or Bad thing for modified cars?

Looks like they'll just do a visual inspection, and then plug in and make sure theres no codes. No tailpipe sniffer.

I'm currently reading a bunch of State Documents trying to understand it.
As far as vehicle computers go, I'm no guru.
Thats what I really want to understand. How our computers work, and what information they will be transmitting.

Does anyone have a strong understanding of this?

As far as the OBDII reading part of the test (not visual) does any one know:

1. If we have a tune will we pass? Or is a reflash to stock required?
1a. Then we have to drive around how many miles to populate values?

2. If a tuned car ignores data from a removed sensor, how will the test results show?

3. Will an Accessport Mask codes?

I kinda wish they would just let us run any tune, any mods, with any catalytic converter as long as it passed sniffer.
That would be the logical way to control pollution.

Diavolo 01-18-2013 03:57 AM

for reference:
stuff i learned from reading the document found at the link above:

twice as many vehicles are likely to fail an OBDII test compared to the tailpipe test.

the new test will also prevent or drastically reduce "clean scanning" a.k.a. getting info from a surrogate vehicle.

newer vehicles contain lots of information:
Calibration ID (Cal ID): a number assigned to a particular vehicle model to indicate the software calibration of the vehicle.
Calibration Verification Number (CVN): This value is computed based on contents of the on-boards computer's software. Unique to a specific Cal ID, even down to identifying models or trim levels.
Vehicle Identification Number: (VIN) we all know this one. some cars have it on their computer.

Diavolo 01-18-2013 04:45 AM

2007 and newer Subaru's use CAN (Controller Area Network)
Beginning in 2008, the Society of Automotive Engineers (SAE) requires 100% of the vehicles sold in the USA to use the CAN Bus communication protocol

I'm still trying to educate myself on this, but basically it seems like any car with CAN is going to give EVERYTHING up.
All parameters are easily read.
This looks like bad news for tuned vehicles.

Got the Info below from a post I found on another forum after doing a search:

This is what will be read using Mode $09:
- CAL ID for each segment.
- CVN for each segment.
- VIN of your vehicle.

they then use the VIN to look up a database containing valid CAL ID and CVN values for your VIN
(this is already in place for 2005+ cars)

if your car is a 2005+ they will definitely see the differences in CVN values.
if your car is 2000-2005 they may still be able to pick up on these differences, even tho they didn't legislate for a database for cars prior to 2005; that doesn't mean they don't have a means of looking up and checking (they have had the ability to store the CAL ID and CVN values from all your previous smog tests, and they have the computing ability to detect differences, they just can't necessarily compare them to the OEM values)

Cars after 2005: they legislated that the OEM's provide the cal ID's and CVN's for each VIN in generalized database format; the BAR can compare values read from vehicle against the generalized database.

for your car to pass the PCM had to do these things:
- show no codes present,
- set all the Readiness tests to Ready (2002+ one is allowed to be Not Ready),
- set all the O2 test results to values indicating pass;
- control fueling/timing to produce emissions levels that are within the sniffer limits.

A scanner is also able to read these things (defined by OBD-II since its inception):
- Mode 6 test results (theses will show that you have codes/sensors turned off),
- calibration ID's and CVN's;

Diavolo 01-18-2013 05:26 AM
click on the navigation tabs.
inside information under the "industry" tab

Smog Check Manual:


Diavolo 01-18-2013 07:18 AM

Drive Cycle after ECU reset:
(found on different forums, not sure if either are correct)
__________________________________________________ ___________

Version 1: (claimed as generic OBDII reset)
Cold Start. In order to be classified as a cold start the engine coolant temperature must be below 50C (122F) and within 6C (11F) of the ambient air temperature at startup. Do not leave the key on prior to the cold start or the heated oxygen sensor diagnostic may not run.

Idle. The engine must be run for two and a half minutes with the air conditioner on and rear defroster on. The more electrical load you can apply the better. This will test the O2 heater, Passive Air, Purge "No Flow", Misfire and if closed loop is achieved, Fuel Trim.

Accelerate. Turn off the air conditioner and all the other loads and apply half throttle until 88km/hr (55mph) is reached. During this time the Misfire, Fuel Trim, and Purge Flow diagnostics will be performed.

Hold Steady Speed. Hold a steady speed of 88km/hr (55mph) for 3 minutes. During this time the O2 response, air Intrusive, EGR, Purge, Misfire, and Fuel Trim diagnostics will be performed.

Decelerate. Let off the accelerator pedal. Do not shift, touch the brake or clutch. It is important to let the vehicle coast along gradually slowing down to 32km/hr (20 mph). During this time the EGR, Purge and Fuel Trim diagnostics will be performed.

Accelerate. Accelerate at 3/4 throttle until 88-96 km/hr (55-60mph). This will perform the same diagnostics as in step 3.

Hold Steady Speed. Hold a steady speed of 88km/hr (55mph) for five minutes. During this time, in addition to the diagnostics performed in step 4, the catalyst monitor diagnostics will be performed. If the catalyst is marginal or the battery has been disconnected, it may take 5 complete driving cycles to determine the state of the catalyst.

Decelerate. This will perform the same diagnostics as in step 5. Again, don't press the clutch or brakes or shift gears.

__________________________________________________ ___________

Version 2: (claimed as Subaru OBDII reset)

Subaru recommends the following conditions and drive cycle to get the monitors on its vehicles completed in the shortest amount of time:

1. Make sure the fuel tank is between one-quarter and three-quarters full; half a tank is ideal.

2. Start the engine and immediately drive the vehicle for at least 15 minutes at a speed greater than 50 mph. During the warm up, try to avoid sudden acceleration, hard braking and/or lane changes.

3. Drive the vehicle at a steady 55 mph for three more minutes. During this stage of the drive cycle, it's crucial that you keep throttle angle changes to a minimum.

4. Bring the vehicle back to the shop, hook up the scan tool and look at the status of the readiness monitors. Repeat the drive cycle, if necessary."

GT35 STi 01-18-2013 04:42 PM

:cool:Good to know, keep sharing the info

haycock 01-18-2013 06:51 PM

This doesnt sound good for people with tunes that cant be returned to stock...
Do you know when they will start testing this way?

Diavolo 01-18-2013 07:43 PM

the new testing started the first of this year. its already in effect.

they may still be doing some tailpipe testing too in addition to the OBDII scan, just until all the technicians and inspection equipment is standardized. by the end of this year it will be OBDII scan only.
...but yes, it has already begun:
Pass or fail is based on info obtained from your OBD port.

This is my understanding based on what I've found, but it may not be 100% correct and i'm sure they'll change stuff as they work out the bugs in their system:

they will do a visual inspection.
they will plug into your OBD port, look for any codes, and read all the data your sensors are sending out.

then compare that data to factory data for what those values should be.
this will determine if your vehicle is polluting or not.

for people who are tuned they could possibly recognize that your parameters are different.
for 2007 and newer Subarus your car will volunteer all the data they need to fail your vehicle based on a parameter check because of the way the computer is wired.

if they don't bother to compare why the values of a tuned car are different, but those values are still acceptable they may give it a pass, but we wont know what will slide under the radar until someone tries to smog their tuned car. some tuning methods may pass? but i don't know enough about different tuning methods.

starting back with 2006 model year ALL vehicle manufacturers have had to provide data about what factory parameters are to the Smog police to prepare for this kind of testing.

for model years 2005 and older the manufacturers didnt have to report this data. it is still available to smog police to look up, but it wont be automatically compared during the test. so maybe for vehicles 2005 and older, a tune could sneak by? if it is deemed to be non polluting, because theres no readily available data from subaru saying "hey it should be this!"
like i said we wont know until anyone tries.

2006 Subarus I don't know what will happen. the car's computer is still wired the same way the 2005 LGT (not CAN). so data might be harder to read, but still legislation demanded that Subaru reveal how 2006 model years computer should work and what the acceptable values should be. whether or not you can mask a tune on this year is unlikely.
but again i don't know enough about method of tuning and the car's computer to know what will happen.

2007 Subaru applied CAN bus (wiring of components and how they communicate) to all vehicles. CAN will give up all your vehicles data easily.

Every vehicle 2008 and newer has applied CAN bus per the SAE.

Heedz 01-21-2013 03:08 AM

I don't think it's in effect till September of this year? I can't remember. I'll have one coming in June so.

GTEASER 01-21-2013 08:57 AM

My wife's car gets a Smog Inspection in a couple weeks, I will watch the process and report.

StoplightAssassin 01-21-2013 09:24 AM

I've only ever known the OBDII test in NJ. It isn't bad.


Originally Posted by Diavolo (Post 4251562)
As far as the OBDII reading part of the test (not visual) does any one know:

1. If we have a tune will we pass? Or is a reflash to stock required?
It depends on the numbers CA requires to pass. Many of us go through OBDII inspection in NJ with our tuned LGTs and never have trouble passing.

1a. Then we have to drive around how many miles to populate values?
Again, it depends. I couldn't give an exact number, but 100 miles will definitely do it.

2. If a tuned car ignores data from a removed sensor, how will the test results show?
If you're talking about the EGT probe resistor mod, the code can be shut off with an AP or RomRaider and it won't pop up again.

3. Will an Accessport Mask codes?
Yes, but at the same time it will reset the readiness monitors. You will fail if the car hasn't been through the required cycles to set the monitors. Any stored, current, or pending codes will be an automatic fail, at least they are in NJ. Considering you must have a majority of the readiness monitors set in order to pass inspection, there's a good chance the CEL will pop up again in the miles spent trying to set the monitors

rhino6303 01-21-2013 11:25 AM

Washington State has also done the OBDII testing for a long time. I can't say if the California one will check for though. It is painless process.

Drift Motion 01-21-2013 12:06 PM

I really don't think you guys can compare out of state smog checks with cali's ridiculous smog checks

and OBD-II port scans has been in place for many years. this time, I believe, they are just making it more strict/reading more data than just the CEL/Readiness monitor

TheOneDoubleN 01-21-2013 12:11 PM

Cali smog FTL!

technicalgarage 01-21-2013 01:20 PM

Subscribed... CVN...

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