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Emissions & Modifying your car

32814 Views 43 Replies 21 Participants Last post by  fb6ben
OK this has been coming up an excessive amount of time. First thing's first:

- If you're worried about passing emissions, do not modify your car.

Tuning solutions (FlashPro included) are sold as "OFF ROAD USE ONLY" products, meaning they are not there to help you pass emissions, fudge your emissions, or in any way let you sneak through emissions testing with a modified vehicle. In fact, it's illegal. It's actually illegal for anyone to even try and help you fudge any emissions testing -- there are federal and state regulations regarding emissions equipment & testing. So, having "tuning' won't guarantee you will pass emissions, but also does not guarantee you will fail emissions -- the simple fact is don't expect the "tuning" to let you pass emissions just because you "tuned" it.

But hey, we're going to modify our vehicles, so how do we pass emissions and readiness tests?

It's very simple, as long as all your factory emissions equipment is working EXACTLY like stock, readiness will set, and if that is what your emissions test requires, you will pass.

Now what do I mean by exactly like stock? This means everything on the car, primary o2 sensor, secondary O2 sensor, EVAP system, etc, all work, are all *enabled*, and none of the codes these systems throw when they find a fault are disabled in the map. If the codes are disabled, the ECU will *NOT* set the readiness. Another fun fact, is EVAP readiness typically will *not* set until the catalyst system sets. So even if you have everything *but* the catalyst tests (secondary O2 sensor off or throwing codes due to HFC/downpipes/headers) working right, you may still have 2 systems that will not set readiness.

By default we disable the secondary O2 sensor in tunes because it *will* apply trims that screw up the mapping (particularly on vehicles with aftermarket downpipes). Modern ECU's use a wideband front O2 sensor, and the narrowband secondary O2 sensor as a sanity check for lean/rich conditions. When you change the downpipe to use an aftermarket cat or no cat at all, that reading is now SKEWED and not reliable.

In conclusion, it is not humanly possible for us to keep up with all the various state emissions regulations -- this is up to you. If you're worried about emissions and want a fast car, my recommendation is to buy a Corvette, Mustang or GTR. If you are modifying a car and are able to pass emissions still, awesome, let's build a fast car. If you're modifying a car and aren't worried about emissions, hell yeah, let's build a race car?
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Most states you don't need smog for the first 6 years of it beign new.Most will get rid of the car before then

You had me excited for a brief moment until I looked it up for my state. Initially I thought this may be seperate from the "inspection" process.

It is a mere 2 years here in the state of Texas.
Same in NY. First inspection at the end of year one is equipment only. Second inspection at the end of year two includes the sensor up the ol' tailpipe (so to speak).
Literally (IMO)

A county over they have no emissions. I guess I get it, but don't have to like it!!! We are a larger county and makes more of a difference in overall smog. I really am wanting to go catless :D my buddies claim "the know people" and can still get it done... I just don't want to have to sweat it and be SOL if I can't get the same deal.
You could always move. ;)
That is not a valid excuse (to the wifey anyways) to sell our house and move further out. I don't mind the extra drive, but she values being 5 minutes from work. I could hear that conversation now.... you wanna sell the house and move in order to skate emissions hahahahahahahaha!!!!!!
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It seems that a nice and subtle explanation of emissions readiness doesn't make a clear point to some. So let me be BLUNT.

Do not email, pm or text me in regards to passing or "fudging" your readiness monitors on your modified vehicle using a device sold as OFF-ROAD USE ONLY. We CANNOT (legally -- these are federal regulations, not state level) and WILL not support this for applications that are clearly used on the road., nor will we be replying to such inquiries, sorry.

You chose to modify your vehicle out of your own volition, and we are happy to improve your vehicle's performance and drivability.

I wonder what percentage of your customers use as "Off-Road" only, track or drag I'm assuming, since a Civic is the furthest from an off-road vehicle out there. I guess a portion of these also do not have to adhere to the Emissions depending on the county they live. For the others that do have to pass Emissions, what do you suggest when this issue arises? Turn to the forum where others have experienced this?

From a potential future customer... thanks :)
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Tuning devices in a vast majority are all sold as off road use only, the ones that aren't haven't had the feds catch on to them yet -- there have been companies providing tuning software that have been shut down by the feds for being a party to violating the clean air act. The problem isn't the devices being available to modify and tune the car -- the problem is when someone goes "Vit what do I need to do to pull of such and such", etc. If I reply with "blah blah", now I'm a party and can be held liable.

Hondata clearly lists the device is off road use only, and that they cannot support the device in regards to the emissions systems (the FlashPro does not touch them it leaves them working just like OEM) -- I certainly can't provide support for something the manufacturer doesn't.

So cliff notes: you're on your own, or seek help from parties not affiliated with any tuning/ems organization (IE: no one's going to go after your friend working out of his garage, lol).
Thanks for the non-blunt version! I appreciate the response...
Most isn't all and isn't this where people come to make themselves aware.
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