Mine passed every year with the trifecta base tune. No problems until this year. Had to remove the charge tubes, intake and the like even though it passed the smog test. No codes.
This year they are requiring the hood be opened and if it doesn't look stock to the tech, you get sent to the ref. Meaning if you have color charge tubes even though they are stock you are testing the water. Mine is good for two years, and will be licensed in Arizona at my uncle Bill's place then.
Visual inspection isn't new. It's been part of the smog test since the beginning, even for OBDII cars.
It is really ridiculous. I have a friend that has a 62 baja bug with ao 2012 Honda engine in it. Engine is built to the hilt, I don't think it would ever pass smog, but it is street legal.
An officer can send your buddy's bug to the referee if he wanted to (admittedly unlikely,) and it'd fail then. Exemption from biannual testing isn't exemption from the laws, it's just a lack of compliance verification.
There was a thread here a few years ago where someone who seemed to know what he (or she) was talking about said in California, anything you modify between the air cleaner and the CAT is illegal, I think he (or she) said that was true everywhere, but especially in California where there is a visual inspection. The GMPP tune and sensors (as slab8 mentioned) is my understanding of the only CARB (California Air Resources Board) legal tune for our cars.
I'm open for anything that disputes that!
Also, as long as some California folks are reading, can anyone recommend a good shop for us in southern California, specifically north San Diego or southern Orange county areas?
So long as the readiness monitors report as passed, the ECM reports the correct VIN and powertrain, and the car doesn't
sound off, probably any tune can get through the OBD-II plugin test. Visual is up to the individual tech's level of attention to the job. The GMPP tune is the only
legal option. It's not the only one that can get through the test, even though the other options are not legal. If the plug-in test starts verifying checksums/versioning info of the calibration (I don't believe that happens currently,) then alternative tunes will become a problem for passing a plug-in only test.
EPA defines anything that changes the emissions equipment on a car as 'tampering'. Aftermarket parts get around that by claiming "for offroad use only", even when the primary market is street-driven cars. EPA has actually cracked down on that a bit:
https://www.epa.gov/enforcement/harley-davidson-clean-air-act-settlement Harley got busted for selling tuners to street motorcycle buyers over the counter at dealer parts departments.
https://www.epa.gov/sites/production/files/2018-05/documents/evanstuningllc.pdf here's a settlement against a shop selling Diablosport tuners, Hondata, AEM ECMs, COBB tuning boxes, "test pipes", etc. Here's the list of enforcement actions for 2018:
https://www.epa.gov/enforcement/2018-clean-air-act-vehicle-and-engine-enforcement-case-resolutions
EPA generally only takes action against commercial entities, not individual car owners. So while it's true that you're not likely to get into any trouble in parts of the country where there isn't emissions testing or enforcement, the parts are still breaking the law when used on public roads. The difference is that California and some other states actually check that regular people haven't tampered (and also that they keep their vehicles in good working order with respect to emissions equipment.
If you are talking about CAI, I think the GMPP one is the only one legal in California, but only from 2008 on the Redline/GXP. 2007's are not included. As to the tune, Trifecta on the base tune offered you a switch, just set the car back to stock when you take it in. Passes no problem.
Importantly, the CA-legal parts MUST have a decal with the CARB E.O.# number on it. Don't buy a used one missing the decal, cause it'll fail just as bad as a no-name part. This is because it's not realistic to have the smog tech validate that a part (of millions of aftermarket parts) is the correct certified one. They check for the decal (and optionally pull the EO to see details which might be relevant to the legality of the part.) If the trifecta tune can't pass an OBDII scan-only smog test, that's really baffling, unless it actively disables emissions equipment, as what comes out the tailpipe isn't checked.