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      05-25-2022, 04:31 PM   #25
Second Lieutenant

Drives: 1989 325i & 2014 335i
Join Date: Jul 2021
Location: Philadelphia

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2014 BMW 335i  [0.00]
1989 BMW 325i  [0.00]
Second post in one day, CRAZY!

Today's post is all about getting ready to pass an emissions test, because that's what I'm doing.

As a quick recap, my car has a 7" FMIC, CP, DP, and a 93 Octane Stage 2 BM3 tune. All these things would fail a CA inspection for visual and the plug in scan.

From what I know, PA is only checking the emission monitor status. I probably SHOULD fail a visual for mods, but I've heard it isn't really enforced.

Lets talk about tunes and emissions. I downloaded a copy of ISTA+ for diagnostics. This is the same software that BMW techs use. After you run a full scan, you can go to 'Vehicle management' --> 'Service functions' --> 'Power train' to see some interesting info. Look on the right side and see the red dot inside my star in the row for 'Checking engine tuning'. This will alert the tech that some parameter of your tune has changed.

To learn about how to set the emissions monitors, you can select 'OBD scan tool' on the left pane, then 'Petrol engine Readiness Codes' on the right pane, then 'Display' on the bottom. This tells you about the tests the car performs and the conditions to set the monitors.

From the previous screen, you go into a test function to display some interesting info. Select 'OBD scan tool' on the left pane, then 'OBD scan tool' on the right pane, then 'Display' on the bottom to get to the next screen.

Lets talk about why tunes fail the CA Smog test. Select 'Read out vehicle information (CAL ID/CVN)' and hit 'Continue'. Over the past several years, the CA BAR and CARB have been cataloging the Calibration Verification Number for every OBDII car. Based on my VIN, they know what all the 1s and 0s for my control unit (0x12) should add up to in hexadecimal. In my case, the correct value for the CAL-ID is E2C3797B. My value was "FC64018F". They don't know I'm on BM3 with a stage 2 93 octane tune, but they do know SOMETHING has been changed. So I would fail.

To illustrate this point, I wanted to remove all pops and burbles from my tune. I did that and reflashed the tune, and now my CVN is "3113B4D1". They don't need to know what you did, they just need to know the sum of 1s and 0s doesn't match the CAL-ID. So you fail. That's why you HAVE to flash back to stock AND lock the ECU.

Great, you flashed back to stock. Now all your emissions monitors got reset. Follow the drive cycle tests above to get them ready for the test. To check them, go to the 'OBD scan tool screen' and select 'Read out OBD Readiness Codes', then hit 'Continue'.

You'll get a list of monitors. 'Support: / yes' means your car supports the test. 'Check: / Concluded' means the monitor is ready. Check with your DMV to figure out how many of these are needed to pass the test. 'Support: X no' means your car doesn't support this test, so ignore it.

No to wrap up, lets talk about Downpipes and emissions. No catless downpipe will pass emissions without some other trickery. Most catted downpipes are enough to keep the car from thinking it has a serious problem (no Check Engine Light), but it will not set the Readiness Monitor. Several companies (I have an Active Autowerks) sell 49-state compliant downpipes. This will fail the visual in CA, but was enough to set the monitor. Assuming I had flashed to stock, locked the ECU, and had an inspector that would pass my visual, I could pass the computer test in CA.

I'm going to get my monitors ready on the stage 2 tune and see if it will pass inspection here in PA.
Appreciate 0