Failed Emission!!! help!!

[DrifterXRPS13]

i failed my emission about four five months ago and have not had a chance to figure out what's wrong with it, when i asked for help they wanted to see my results but my mother had thrown them out, but no i finally got a copy of them and here they are

Standards Readings

Hydrocarbons: .80 .88

Carbon Monoxide: 15.0 29.1

my car is an 89 fastaback se, 5 spd, mainly stock with an air filter and aiv removal(after i failed) haven't replace my plugs, cap, rotor, wires, o2 sensor, please help me before i take it to the shop. thank u.

[180fan]

Try the tune up first and get a pre-test. See what happens. It would be alot more help to have the actual numbers though, that'd point the rest of us in a better direction than stabbing in the dark. But for sure try the tune up.

[s13sr20chris]

agreed. what was the co2?

[DrifterXRPS13]

i did post the readings, the standards for hydrocarbons are .80, my car read .88 and the standards for carbon monoxide is 15.0 and my car read 29.1, thanks for the help

[navysnail]

there is usually 4 readins: co, hydrocarbons, co2, and NOx

from the 2 that you posted, the hydrocarbons are too high, meaning that you are running rich, replace everything that you mentioned above, including o2 sensor and that should get you to pass if your only .08 over

[DrifterXRPS13]

thanks 240kid, the reason i only posted two are because that's the only ones that matter, i don't get a pass/fail on the other two, they come up as n/a....btw off topic, hows the brm exhaust?

[navysnail]

hmm, wierd, maby they dont check those in your area

i love the brm exhaust, fit perfectly and sounds just the way i would like it to.it makes a noticable increase in power delivery, the powerband is more linear

[s13sr20chris]

i was wondering the co2 just because its an indicator of complete combustion(though you must not be having that). i guess i just like to look at the bigger picture. i know folks who say a new cat and a gallon of denatured alcohol in the tank during the test will pass just about anything.

[Julio Bro!]

I ran into a similar problem today, emissions are tested at high and low rpms; I didn't pass low rpms. I don't know how the standard units are but these are my numbers:

HC = 405 (need 300 to pass)

CO = 2.27 (need 1.50 to pass)

I removed my PARC valve a few months ago and I know this works at low rpms and decceleration; could this be the problem?

I already replaced spark plugs, oxygen sensor, temp sensor, cleaned the idle control valve, and MAF is fine.

Suggestions?

[s13sr20chris]

yes, the pair valve is important for low rpm emmissions. it injects air into the cat to help it.

[Julio Bro!]

Today I reinstalled the AIV so I expect to pass tomorrow at the emissions test.

[DAEDALUS]

Make sure the engine is fully warmed up. The cats don't do anything if they're cold. O2 needs to be hot too, but not as much as the cats. In case the valve doesn't do it, and ssuming the cats are hot and in good shape and everything else is working, your numbers would suggest that the car's running rich.

[Julio Bro!]

As I explained on my "Truth..." post, this engine runs on the rich side and the AIV helps to counter some of that. On latter engines the ECU was programed for a leaner mix and thus the AIV was not needed.

I hope my numbers go dow; I'll inform what happened.