hey guys im new the the forum. I have an all stock honda civic ex 5 speed that failed smog in cali. The has no mods done to the car. It has 125k miles on it. the car runs perfect except on cold start up my rpm tends to fluctuate which indicated it could be the iac. The fluctuation goes away after the car is warmed up. I changed the oil 2k miles ago but i haven't drove the car in almost 4 months. The previous owner said he did the tune up before he sold me the car (122k). Like i said everything is stock right down the the paper filter (which is dirty). I only failed the HC and the NO at 15mph. Heres the results. Any help would be greatly appreciated.

15mph
RPM: 1883
CO2: 15.10%
O2: .13%
HC: 97 l 107 ( failed)
CO: .59 l .26 ( pass)
NO: 731 l 797 (failed)


25mph
RPM: 2051
CO2: 15%
O2: .03%
HC: 62 l 62 ( barely passed)
CO: .59 l .19 (passed)
NO: 798 l 225 (passed)

 

get a new cat?

 

the HC number is probably related to the dirty filter, could help bring the NOX down too.

 

for more info on the car. When i did the smog, the timing was set at 14 deg btdc. I'm wondering if that is the stock reading. Also many people believe i could have a clogged fuel injector, so i put some stp fuel injector cleaner and it made the car run much more smoother and have a better fuel economy. The car idles near perfect. thanks for the quick responces

Edit...... I pulled my spark plugs and they were worned down. So the previous owner lied to me about changing the spark plugs. I went to change the plugs ,wires, cap and rotor. Goinf to get it resmog tomorrow.


Modified by 95ex5speed at 6:24 PM 10/12/2004

 

nox it due to high temp in combustion camber, it could be lots of thing but often time it's carbon. try sea foam from napa, works wonders

 

would a clog cat cause a high NO reading?

 

carbon residue in your cylinders, there's a napa on thorton and cedar ask for sea foam

 

well guys i went back the the smog shop and passed. The only thing i've done since the last smog is that i put in a new obd2 cat, new plugs,wires,cap and rotor and a new filter. I haven't changed the o2 sensor and the egr valve with probably contribute to the high HC and NO. I also didn't put the sea foam, but I would recommend the new owner to put it in. I really appreciate all the input i got from this forum. Now the car is smogged, its getting sold by tonight. Heres the results

15mph
RPM: 1926
CO2: 15.37%
O2: .03%
HC: 97 l 96 ( passed barely)
CO: .59 l .13 (passed)
NO: 731 l 535 (passed)

25mph
RPM: 2072
CO2: 14.96%
O2: 0.00%
HC: 62 l 44
CO: .59 l .05
NO: 798 l 81

I did the second smog 15 mins after i put the new cat.

 

well guys i went back the the smog shop and passed. The only thing i've done since the last smog is that i put in a new obd2 cat, new plugs,wires,cap and rotor and a new filter. I haven't changed the o2 sensor and the egr valve which probably contribute to the high HC and NO. I also didn't put the sea foam, but I would recommend the new owner to put it in. I really appreciate all the input i got from this forum. Now the car is smogged, its getting sold by tonight. Heres the results

15mph
RPM: 1926
CO2: 15.37%
O2: .03%
HC: 97 l 96 ( passed barely)
CO: .59 l .13 (passed)
NO: 731 l 535 (passed)

25mph
RPM: 2072
CO2: 14.96%
O2: 0.00%
HC: 62 l 44
CO: .59 l .05
NO: 798 l 81

I did the second smog 15 mins after i put the new cat.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 95ex5speed &raquo;</TD></TR><TR><TD CLASS="quote">I haven't changed the o2 sensor and the egr valve which probably contribute to the high HC and NO.</TD></TR></TABLE>

EGR valve in a Civic EX?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 95ex5speed &raquo;</TD></TR><TR><TD CLASS="quote">I haven't changed the o2 sensor and the egr valve which probably contribute to the high HC and NO.</TD></TR></TABLE>

EGR valve in a 1995 Civic EX? I don't think they have one.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by StorminMatt &raquo;</TD></TR><TR><TD CLASS="quote">EGR valve in a 1995 Civic EX? I don't think they have one.</TD></TR></TABLE>
you are correct they dont.

 

oh opps