alright i have to pass smog, my HCs and my COs were really high on my first test which i failed but my NOx passed, now i put a new CAT in and now everything passes except for NOx. does anybody have any idea on how i can drop them down? i need this thing to pass cuz my registration is out of date

 

did you do a general tune-up when you changed your cat? change your spark plugs, cap and rotor, some injector cleaner, check timing, etc.

 

oil was changed last week, plugs and cap and rotor are maybe 2 monthes old, timing was dead on, and i ran a bottle of octane boost also. i let the car run forever, NOx happen when the combustion chamber reaches heat of over 2500 degrees i wonder if that happened cuz i let the car run to long?

 

ISO Heet from the auto parts store.. red bottle.. run a bottle or two and about half a tank of 89 and you are set

 

i put in 91 octane it was a little over half a tank of gas and i dumped in a bottle of octane booster. i heard a trick about using a full tank of gas but mixing it with 3% of trick racing methonal. i wonder if that would work? the guy had the old turbocharged merker. if i ran a lower octane gas would that drop the NOx level?

this is what my readout was
15mph- NOx max is like 864 i measured 1455
25mph- max 764 i measured 762

 

i can help you for the right price

 

Get that crappy octane booster out of the car. Just run a bottle of chevron fuel injector cleaner through 1/2 to 3/4 of a tank and give it another shoot. Some of the octane boosters can really gunk things up. Plus higher octane gas doesn't burn cleaner, infact it probably burns more dirty than 87. High octane fuels burn slower that lower octane fuels. You might also want to check you PCV valve, if it's old they can also gunk up the intake manifold a lot.

 

what is NOx anyway? i just want to bring it down so i can drive thats all, and i dont want to cheat my way out of it.

 

NoX is mainly created by too much heat in the combustion. Normally a faulty EGR (if you are equiped with on) or a lazy O2 sensor will make the engine run lean creating too much heat and you get a higher NoX reading.

SMOG no no's:

Don't run 91 octane unless you HAVE TO. Run the lowest ocatne your engine can handle. Don't put an octane booster in the tank and try to test... you want LOW octane. Don't test after putting injector cleaner in the tank. If you did put something in the tank, run that tank out and get some clean gas in there first.

For your INITIAL test, don't try to do anything fancy like putting HEET in the tank. Do a good tune up (plugs, O2, cap, rotor, PCV valve, air cleaner, clean intake manifold and inside TB, ... etc.) and make sure everything is in clean and good operating order. If you are going to run some injector cleaner, do it a month before the test so it can run it's course in your fuel system. Run the tank low and put in 1/4 tank of the low octane. On test day, drive the car around for about 20 miles to get the cat warmed up and go to the test ... don't turn it off... leave it idling to keep the cat warm. Testing like this will give you a good chance to pass and if you do happen to fail you will have an excellent baseline to work from for figuring out exactly what you need to do to not fail again.

 

i had a similar problem a few years back, i took off my DC headers, put the stock one back in and i passed it right away, i guess the 02 sensor on my DC headers was the problem..

 

well i have the mpfi swap, stock header and stock intake, its a new cat with a 2" exhaust to the turbo muffler, and then 2.25 piping from the muffler to the bumper. so as you can see the only things that arent stock on my car are the mpfi swap and the muffler.

cap, rotor, plugs, all have maybe around 1500 miles on them, 02 sensor at most 2500 miles

 

Change the plugs and give it a try. You really should upgrade to the SI cam if you already haven't also. The DX cam produces a strange air fuel with a pm6.

 

havent done the SI cam, i heard that jumps the timing way off if you use the dx gear, i am gunna get a adjuastable cam gear and then put the si cam in. I am also going to run a step colder plug also to see if i can really drop the NOx

 

oh i heard that with the conversion to mpfi, header, aem intake, pm6, 2.5" pipping u couldn't pass smog

hmmmm, im running ok, it's just the engine is drinking lots of gas
i gota do smog pretty soon, do u guys think i should put back to dpfi?

 

Who ever told you that about the cam gears are full of crap. They are 100% the same, all 88-95 d-series cam gears are the same.

 

no they told me the cam was different, i dont know about the gear. i just didnt want to run that cam without a gear

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by eraser &raquo;</TD></TR><TR><TD CLASS="quote">i can help you for the right price</TD></TR></TABLE>
By screwing his friend out of his share of $$....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by silver89civic &raquo;</TD></TR><TR><TD CLASS="quote">oh i heard that with the conversion to mpfi, header, aem intake, pm6, 2.5" pipping u couldn't pass smog

hmmmm, im running ok, it's just the engine is drinking lots of gas
i gota do smog pretty soon, do u guys think i should put back to dpfi?


</TD></TR></TABLE>

going back to dpfi means rewiring the car again to convert back, slap on stock exhaust manifold and intake tube and box and you should pass just fine, im just having problems cuz my car wasnt up to par. here is my latest test results

15MPH
HC- MAX- 138 MEASURED- 21
CO%- MAX- .84 MEASURED- .00
NOx -MAX 859- MEASURED- 1455 (THIS IS WHERE I FAILED)

25MPH
HC- MAX- 112 MEASURED- 18
CO%- MAX .73- MEASURED- .00
NOx- MAX 798- MEASURED- 794

as long as you have a good cat you should be fine, if you dont have a cat then your screwed, i got stuck with a test only smog also so its kind of a pain in the ***

 

The cam phasing is not different. It will work fine.

 

ok well i cant switch it out right now anyway, it will throw me out of IS3