Passing emissions with a tune
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Passing emissions with a tune
For people who live in States that do emissions testing through the OBD2 port, how does one pass emissions with a tune?
One question I have is, if you have aftermarket mods that trigger a CEL that gets removed by a tune, then wont flashing back to stock before inspection just being back the CEL, hence causing one to fail emissions inspection?
Inquiring minds need to know
One question I have is, if you have aftermarket mods that trigger a CEL that gets removed by a tune, then wont flashing back to stock before inspection just being back the CEL, hence causing one to fail emissions inspection?
Inquiring minds need to know
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I had a car with a special map that was designed to get through the car through emissions inspection — ala Volkswagen AG. Car had cams, machined heads, deleted one CAT, air pump delete, and more. The ECU code was altered to pretend that all of that equipment was there and functioning. Aside from one small high flow cat, this was, for practical purposes, a race car powertrain.
Then, one year, I forgot to load the special map and the car passed emissions anyway. 🤣
If it’s running well, not throwing CELs, and you don’t live in California, it’s likely going to pass.
Then, one year, I forgot to load the special map and the car passed emissions anyway. 🤣
If it’s running well, not throwing CELs, and you don’t live in California, it’s likely going to pass.
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I hear that in Illinois the inspector can tell through the OBD2 port that the ECU has been reflashed and can still fail you, even without CELs.
Not sure but I just want to be cautious moving forward doing this, and I don't want to burden M Engineering's thread with this discussion--but it's an important one for sure.
Not sure but I just want to be cautious moving forward doing this, and I don't want to burden M Engineering's thread with this discussion--but it's an important one for sure.
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^ The issue is if you have aftermarket mods that trigger CELs (sport cats, etc).
Sounds like you may literally need to return all of the equipment back to stock, AND reflash the tune to stock, in order to pass emissions.
So a bit more involved, I am speculating.
Sounds like you may literally need to return all of the equipment back to stock, AND reflash the tune to stock, in order to pass emissions.
So a bit more involved, I am speculating.
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sport cat does not trigger CEL, you wont have issues with inspection, just get the tune already
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Isn't that a stupid thing to prioritize in a state that has overwhelming problems that they have not a clue of how to address. Yessiree, better make sure everything is Kosher in "Sport +". Simply amazing.
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For people who live in States that do emissions testing through the OBD2 port, how does one pass emissions with a tune?
One question I have is, if you have aftermarket mods that trigger a CEL that gets removed by a tune, then won’t flashing back to stock before inspection just being back the CEL, hence causing one to fail emissions inspection?
Inquiring minds need to know
One question I have is, if you have aftermarket mods that trigger a CEL that gets removed by a tune, then won’t flashing back to stock before inspection just being back the CEL, hence causing one to fail emissions inspection?
Inquiring minds need to know
When I eventually flash my 992S, I will first see if I can pass the emission test. If I don’t, only then will I bother to re-initialize the factory state.
Last edited by CodyBigdog; Feb 6, 2022 at 04:20 PM.
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I don’t know what Illinois does.
Doesn’t matter, I’m pretty much settled on doing the tune. Only reason I am waiting now is because my car is garaged till March.
Again, I am doing not just sport cats (which I already have installed). I am doing a whole exhaust with a new set of sport cats. CEL with that just complicates emissions testing down the road—I would have to swap out exhaust for OEM just for emissions, and then put the aftermarket exhaust back in afterward. A pain. Pay to play, I guess
Doesn’t matter, I’m pretty much settled on doing the tune. Only reason I am waiting now is because my car is garaged till March.
Again, I am doing not just sport cats (which I already have installed). I am doing a whole exhaust with a new set of sport cats. CEL with that just complicates emissions testing down the road—I would have to swap out exhaust for OEM just for emissions, and then put the aftermarket exhaust back in afterward. A pain. Pay to play, I guess
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I dont know what Illinois does.
Doesnt matter, Im pretty much settled on doing the tune. Only reason I am waiting now is because my car is garaged till March.
Again, I am doing not just sport cats (which I already have installed). I am doing a whole exhaust with a new set of sport cats. CEL with that just complicates emissions testing down the roadI would have to swap out exhaust for OEM just for emissions, and then put the aftermarket exhaust back in afterward. A pain. Pay to play, I guess
Doesnt matter, Im pretty much settled on doing the tune. Only reason I am waiting now is because my car is garaged till March.
Again, I am doing not just sport cats (which I already have installed). I am doing a whole exhaust with a new set of sport cats. CEL with that just complicates emissions testing down the roadI would have to swap out exhaust for OEM just for emissions, and then put the aftermarket exhaust back in afterward. A pain. Pay to play, I guess
tupper pal, almost no exhaust out there will trigger a CEL whether its with sport cats or not. The only thing that triggers a CEL is catless which is what I have and the light/code is tuned out so no issues.
Last edited by reddsektor; Feb 6, 2022 at 06:02 PM.
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The O2 sensors will fail a test without giving CEL, regardless of hardware mods.
Interestingly, the dealers can't tell if the ECU has been flashed or not.
This is not conjecture, the above happened to my prior car with the new owner (by then, CPO).
Interestingly, the dealers can't tell if the ECU has been flashed or not.
This is not conjecture, the above happened to my prior car with the new owner (by then, CPO).
