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-   -   failed emissisions horribly, have an idea.. (https://www.rx7club.com/1st-generation-specific-1979-1985-18/failed-emissisions-horribly-have-idea-398381/)

rxseven07 02-23-05 05:46 PM

failed emissisions horribly, have an idea..
 
the only reason i failed emissions is the freakin sniffer, im buying an exhaust anyway... do u think i should just drill a freakin hole in my exhaust and let it come out of there so when they put the sniffer in, it will read really low? or would that have nothing to do with it... by the way im in tn

kenn_chan 02-23-05 05:52 PM

Try this
 
did it fail on CO, or NOX? if its a combinatins of both then try this:

Take your air pump and disconnect it at the front and back of the carb (OR EFI) then hook the two togethor direct, without the valve assembly - check your timing, get yourself about 2 gallons of ethanol alcohol, and mix it with 8 gallons of medium grade gas, then get it checked, unless you have something horribly wrong it should pass.

if its only one or the other and its mild, then you simply need to adjust some things, if its really outta wack.

Kenn

rxseven07 02-23-05 05:57 PM

kenn,, i have no air pump, i have nothing to do with emissions on my car at all besides the 1st 2 cats... where do u by alcohol at?

smnc 02-23-05 06:01 PM

1.) It would be WAY loud
2.) They check for leaks, and won't pass you if you have any.

rxseven07 02-23-05 06:07 PM

im stumped.

RX7Elmo 02-23-05 06:08 PM

they check for exhaust leaks anywa, sometimes they might let it pass. If you drill a hole, the point is not to let exhaust gas out, but to let fresh oxygen into the exhaust airstream, the point is for you to dilute the emissions. So basically, it checks for % of co, 02, nox in the exhaust, not the actual volume.

If you have those sidedrafts in..that's probally why you're not passing, run it lean..or jet it lean and see what happens.

Dennatured alcohol can be used as a last resort, mix it at a realy high ratio if you wish, but the car will run like crap. maybe run the tank to 1/4 and put in 1-2 gallons in. You can find it at any paint store, or hardware store.

rxseven07 02-23-05 06:16 PM

will the alcohol fuck up my car>?

vipernicus42 02-23-05 06:34 PM

Kenn Chan has my idea:

Hook the air pump directly to the exhaust. Remember: The Solution to Pollution is Dilution! ;)

Then run your carbs lean and get some Ethanol gas. That might help.

Jon

nevarmore 02-23-05 07:04 PM

Do you still have the ACV? Theres some trickery that can be done with that.

Check the OHR FB Emissions thread where we went and tested this out for academic purposes, http://www.ohiorotaries.com/phpBB2/viewtopic.php?t=384 . Don't break the law and if you do its not our fault!!

rxseven07 02-23-05 07:12 PM

u guys must have not read all of the posts, I HAVE NO EMISSIONS ON MY CAR!! NO AIR PUMP, NO ACV NOTHING, THE ONLY EMISSIONS THING I HAVE IS 2 CATS

KitsuneRacer 02-23-05 07:22 PM

Then your car will probably never pass, try running it lean and mixing alcohol... that's about all you can do since you don't have the Air Pump.

John64 02-23-05 07:33 PM

If you have no emissons on your car then your cats are toast anyway.

kiker14 02-23-05 08:02 PM

i too am in the same situation, but I have no cats...

so i'm also thinking about trying the alcohol thing...

will i mess up anything?

kenn_chan 02-23-05 11:02 PM

OK sometimes I can be a dick
 
Like somebody else posted a thread or two back about me, but I really do like to help when I can. so heres what I would do to get by....

Go to EBAY, and buy an electric air pump off of a newer model corvette, or camaro (GOD IHATE CHEVY'S)

take the electric air pump, and tap it into your exhaust right at the cats (put a valve there, water valve whatever (its just to close the pipe while you are driving to the emissions test place)

run a 30 amp fuses, and relay to a switch.

go to emissions, in parking lot open valve, and turn on electric smog pump

(of course you mixed the denatured alchy in there earlier)

and pass the emmisions with a smile :)

the electric air pumps run betwenn 20~40 dollars on ebay (Ijust bought one for this purpose) :) :) :) and they though out enough CFM to pass my buddies TII here in japan with a modded ECU, FMIC, filter etc.

Or, and John (Viper critter somethingornother) where did you here that, its been one of my favorite sayings since I first heard it years ago :)

ArmySoldier 02-23-05 11:55 PM

I am thanking God I live in a state where emissions testing isn't done, but if Illinois ever does.... oh well, all I have is a glass pack, no cats at all.

steve84GS TII 02-24-05 12:08 AM

As stated before,youll never pass without some emissions equipment and your cats are DEAD if you still have them installed.
Rotaries pump out a lot of unburned hydrocarbons,much more than most engines, due to their design.The airpump and cats handle 99% of it.In fact the vast majority of the entire rats nest and factory smog mess is directly in charge of operating the secondary air injection system.
Alcohol is good for reducing NoX because it lowers combustion temps,but rotaries are already low in NoX because of their low compression ratio.Hence the lack of EGR valves on the majority of rotaries.
Just drilling a hole in the exhaust isnt going to help.In fact they will likely fail you because they wont be able to get a proper reading on the probe DUE TO the dillution.Back 20 years ago,carbd and early EFI engines ran much richer than modern ultra lean engines.They needed air injection to burn off the wasted fuel.Thats why they have airpumps to introduce oxygen into the exhaust stream.Most modern engines run lean enough that there is sufficiant oxygen in the exhaust to lite off the cat.Thats why most effecient, modern engines(like Hondas) dont need airpumps.

Good luck passing.I dont know what the HC PPM standards are for your area,but with no smog control devices,your HC is going to be like 3000 Parts Per Million.Just for refference,CA require an average of no more than 150 PPM.It can be tough to meet that even will ALL the smog gear installed.

IanS 02-24-05 12:12 AM


Originally Posted by ArmySoldier
I am thanking God I live in a state where emissions testing isn't done, but if Illinois ever does.... oh well, all I have is a glass pack, no cats at all.

Yeah but all you would have to do is move across the river if they did start testing.

RotaryRevn 02-24-05 12:21 AM

.

kiker14 02-24-05 07:11 AM

hey, i have a friend with an FC (i actually gave it to him) and i was wondering... is the exhaust that comes off the manifold able to bolt up to a gsl-se? cuz that thing passed with flying colors...

rxseven07 02-24-05 08:26 AM

i accually found a friend that works there, and hes going to pass me today i hope. how do they pass you illegally like that?

dazdconfsd 02-24-05 08:48 AM


Originally Posted by rxseven07
i accually found a friend that works there, and hes going to pass me today i hope. how do they pass you illegally like that?

They don't tend to broadcast it

vipernicus42 02-24-05 08:56 AM

Sorry rxseven07, I didn't realize that you had NO emissions equipment. Most people don't even attempt the test if they have no emissions equiment at all.

You want to know how they illegally pass you? They hook another car to the sniffer, and put your name on the printout. They file it as if your car was on the sniffer. VERY illegal, but very effective.

Get those cats off your car. If you've been running without an air pump for any length of time then they're clogged anyway.

You must realize that it's not possible to pass a 20 yr old car through emissions without emissions equipment! Why else would Mazda have invested so much time and money into installing them in the first place if you could pass a 2005 emissions test without them?! Thankfully emissions equipment is much better now, so if you get stuck buying stuff to pass, you can probably get away with a good air pump and high-flow cat that will pass you if you tune your carbs lean.

kenn_chan, I think I actually heard it on here somewhere ;)

Jon

kiker14 02-24-05 11:50 AM


Originally Posted by kiker14
hey, i have a friend with an FC (i actually gave it to him) and i was wondering... is the exhaust that comes off the manifold able to bolt up to a gsl-se? cuz that thing passed with flying colors...

lol... i just quoted myself... anybody know?

steve84GS TII 02-24-05 08:55 PM

Not really.The cat itself might bolt up,but Im guessing the later 13B cats are bigger.
Simply bolting another exhaust system up isnt going to solve the problem,unless it is by chance just a bad cat.You have to determine what part has failed before changing anything.If the cat is good but the ACV or some other valve is bad,youll still fail just as quick as if you had a bad cat.A good cat cannot work without proper,metered air injection.
And on a side note,unless you just do it temporarily to get by the test,running a smog pump directly into the exhuast full time will fry the cat and could potentially torch the car.The ACV and rats nest meters the air injection so that it only injects air when needed.Too much air or air all the time will overheat the cat and cause it to melt down.Thats what the overheat sensors are for,to shut down the air injection if things get too cookin'.If its just for a few minutes to get by a smog test,then you should be OK.

Tom 02-24-05 09:00 PM

Man- I would seriously be greasing some palms if I was you.


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