Emission questions
- Thread starter Dirtyryan
- Start date
Technically any mod from the intake to the exhaust can be considered illegal. If you stick to carb compliant parts or go to a smog shop that is more lenient then others you should be good with some mods. Like intake, exhaust, turbo, up pipes.... stuff like that. I’ve seen some picky smog shops fail bone stock trucks because of the snap test. Which is just watching tailpipe while they snap the throttle and if any smoke comes out they fail it. This is part of Ca diesel emissions test but not all shops actually do this.
If your monitors are correct, which for federal trucks it’s not much, then you should be able to get by.
If your monitors are correct, which for federal trucks it’s not much, then you should be able to get by.
from my experience over the last 6 years the smog laws have changed. I had a DP5 switch in my LB7 (2003) and had no issues. Fed regulations aloud for you to have 1 fail on the check I believe. Now they have stricter regulations and you can no longer fail any system checks. So I had to take out my DP5 setup even after reflashing back to stock.. How ever when I did a single tune install and a reflash back to stock no problems. Other wise I thing you need to visually have technically is a CAT. Depending where you live in CA is how strick they are. In Central Valley area from Stockton to Fresno they have State Ref check points. I have only seen and herd of one in the Bay Area and not really sure about SoCal factually but I have herd a lot of horror stories. They usually double them up with DUI check points. So if your truck is lifted with a 5” down pipe back and no cat they will gladly give you a ref ticket. What I have seen some people do is a 3” down pipe to stock back to a CAT (hollowed out) then a 5” or 4” cat back exhaust. Changes the ticket to a fix it modified exhaust ticket which I have gotten a few of. Most lienent smog shops will pass you aslong as they see a cat and your truck scans good. I painted everything under my hood that I put in my LB7 black so everything appeared to look stock. I did run a 6” stack out the bed when I didn’t go to the smog shop. Just a quick swap out re flash every two years... technically any mod is illegally. I would Start with lift pump single fun tune I think basics with lift pump are about 130hp+ on stock trans Then go for bolt ons exhaust and intake. Unless you go for built trans... hope that helps!
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efi live with serial switching through an edge monitor when its tested set it to stock and pull out the monitor only takes a few seconds.
The checksum won't match, so it could still fail. Several have had this happen. The new Cali test connects to the obd data port and reads out the checksums to verify it is a stock GM certified tune. Adding a tune changes the checksums, and has failed several people. Flash in the stock tune file for the truck so all the segment checksums match up to tis.
When did they start doing this? I got mine tested a few months back and had no issues
Checking other forums and sites for more information, it seems that right now all they are doing is reading the CVN/checksum. Likely to create a database for when the vehicles come back for the next smog check they can cross check them against the database (which later may include all of the stock and approved calibrations) and see if the checksum has changed.
Probably doing this as a study or to gather enough data to then later implement some law or other means of trying to stop tuners.
Thinking about it, it could be more effective than having the ecm encrypted or locked down by some other means. That could be cracked. Not sure if checksums could be fudged to appair like stock though.
As of yet it seems the state/CARB has yet to do anything with it to fail the smog test
Probably doing this as a study or to gather enough data to then later implement some law or other means of trying to stop tuners.
Thinking about it, it could be more effective than having the ecm encrypted or locked down by some other means. That could be cracked. Not sure if checksums could be fudged to appair like stock though.
As of yet it seems the state/CARB has yet to do anything with it to fail the smog test
They CAN be, but thats playing with fire for the tuner that does it. I know when I 1st started tuning efilive wasn't changing the checksums in the altered files, and they quickly changed that because they said the only reason to do it was for illegal reasons, so they weren't leaving it that way.
As said above, stick to CARB mods. Being a fed LB7 (no cat) you should be able to get away with exhaust.
Do a downpipe, exhaust, lift pump, PPE or Kennedy boost valve etc. The exhaust (downpipe back portion) could be put back to stock incase they consider that a fail. I am not horribly up to speed with Commiefornia's emissions requirements.
Here in WI we don't have emissions testing in my area and have never had to deal with it.
Do a downpipe, exhaust, lift pump, PPE or Kennedy boost valve etc. The exhaust (downpipe back portion) could be put back to stock incase they consider that a fail. I am not horribly up to speed with Commiefornia's emissions requirements.
Here in WI we don't have emissions testing in my area and have never had to deal with it.
From what I've heard it depends alot on the person doing the test. The electronic portion is pretty cut and dry as it is plug in the obd2 cable and the computer does the rest, but the visual checks are more so on the person inspecting it. I know once you get failed and it goes in the system you have to go to an upper level inspector for the next inspection, and they say those people tend to know what they're looking for with many even catching the tabs sticking out on blocker plates.
Thanks for all the advice. Some comments have gotten me a little weary of running some mods. My fed truck doesn’t have a cat so I will be running a down pipe exhaust with a muffler. I hear if you don’t put a muffler on they can also fail you. I will also be adding a bigger intake.
Still a little confused on which tuner to run. I’ve never had a tune in my other truck and my friends who did tune theirs never seemed to get the life expectancy as a stock. I’m not looking to add a crazy amount of HP. Any recommendations?
Still a little confused on which tuner to run. I’ve never had a tune in my other truck and my friends who did tune theirs never seemed to get the life expectancy as a stock. I’m not looking to add a crazy amount of HP. Any recommendations?
GMC_2002_Dmax
The Still Master
I would move to another state...................:roflmao: :roflmao: :roflmao:
Short of that I would register in another state............:thumb: :thumb: :thumb:
But that state is totally out of control...............
Short of that I would register in another state............:thumb: :thumb: :thumb:
But that state is totally out of control...............
EFI Live from any reputable shop should keep the stock trans running well. That said, it is a stock trans taking more power than it was designed to. If you beat it on the race tune it will die. If you treat it nice it should hold up for quite awhile.