HKCivic

So I have a 1992 DX (stock motor) with 136k miles and a greddy turbo kit on it. I am only running 5 pounds of boost. And my car failed the MD emmissions test.

I should also note that I am using a test pipe (no catylitic converter) and a vortech 12:1 FMU to keep fuel mixtures correct. The car has just recently recieved a tune-up (oil change, coolant change, new spark plugs, new O2 sensor).

In MD the limit for "Hydrocarbons" is 1.0000 GPM, where as my car came out with 2.9997 GPM. Needless to say I failed the Hydrocarbon portion of my emmissions test.
Additionally, I failed the Carbon Monoxide portion of the test. The MD limit for Carbon Monoxide is 20.0000 GPM where as my car came out with 33.3835 GPM.


This may be a dumb question but, will putting my catylitic convertor back on fix this problem on its own?

davefromPA

personally i see no point it running without a cat unless you are racing. put one on and see how that works for ya.

ScionTech

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HKCivic &raquo;</TD></TR><TR><TD CLASS="quote">So I have a 1992 DX (stock motor) with 136k miles and a greddy turbo kit on it. I am only running 5 pounds of boost. And my car failed the MD emmissions test.

I should also note that I am using a test pipe (no catylitic converter) and a vortech 12:1 FMU to keep fuel mixtures correct. The car has just recently recieved a tune-up (oil change, coolant change, new spark plugs, new O2 sensor).

In MD the limit for "Hydrocarbons" is 1.0000 GPM, where as my car came out with 2.9997 GPM. Needless to say I failed the Hydrocarbon portion of my emmissions test.
Additionally, I failed the Carbon Monoxide portion of the test. The MD limit for Carbon Monoxide is 20.0000 GPM where as my car came out with 33.3835 GPM.


This may be a dumb question but, will putting my catylitic convertor back on fix this problem on its own? </TD></TR></TABLE>

That's probably why. LoL.

Do you have any check engine light??

HKCivic

Nope, no check engine lights here!

As for why I would run a car with no cat...its turbo...therefore better for performance from my understanding. I intend on getting a hondata tune and upping the boost to 8 pounds so this is also why I chose not to use a cat.

PerryRT

Yup. Here's a quote from Wikipedia -

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Wikipedia &raquo;</TD></TR><TR><TD CLASS="quote">Three-way catalytic converters

A three-way catalytic converter has three simultaneous tasks:

1. Reduction of nitrogen oxides to nitrogen and oxygen: 2NOx → xO2 + N2
2. Oxidation of carbon monoxide to carbon dioxide: 2CO + O2 → 2CO2
3. Oxidation of unburnt hydrocarbons (HC) to carbon dioxide and water: 2CxHy + (2x+y/2)O2 → 2xCO2 + yH2O


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

Honestly, I think the emissions place gave you the - I would have a hard time believing that they didn't at least suspect it wouldn't pass. Charged you anyway, though, didn't they?

Seriously, buy a cat from a junker, or a new one, depending on your wallet, install, repeat the test. I think you'll be impressed at the difference.

And I agree with DavefromPA - I doubt there's really a reason to remove the cat unless you're full-bore track racing.

davefromPA

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HKCivic &raquo;</TD></TR><TR><TD CLASS="quote">Nope, no check engine lights here!

As for why I would run a car with no cat...its turbo...therefore better for performance from my understanding. I intend on getting a hondata tune and upping the boost to 8 pounds so this is also why I chose not to use a cat.</TD></TR></TABLE>

Power is better true. But heres your problem, since you went for the more power illegally (as in it is illegal to not have a catalytic converter), you sacrificed your ability to drive on the street legally. Hence why it is smart to run it only on track applications. This illegal move has brought you to your current position of "what can i do to pass emmissions??" Simple answer really. Put a HIGH FLOW cat on so you lose maybe 2-3 HP and are now legal again. I understand the reasons to not use a cat, just trying to help you out so you can drive your car again on the road

HKCivic

I still have the factory cat... guess I'll just remove the test pipe and put the cat back in untill I can get a high-flow unit. Thanks for the help!

mistahmac

i have a high flow cat from magnaflow new for sale. good luck on passing emissions.