Lets hear some opinions on how to pass, I have a few in mind but I always would like to hear what other people think.

Hydrocarbons are suppose to be .80, mine were 1.60
Carbon Monoxide was suppose to be 15.0 and mine were 32.5

I just change the cat with a brand new one, actually it was on my friends car who just took the emission testing and he passed. His hydrocarbons were .60 . My 02 sensor keeps coming on every now and then, its acting lazy. My question is if the check engine light did not come on, would the 02 sensor still cause the problem ?

I forgot to mention, I drove the car for about an hour before going and when I get there the lady says she needs to turn the car off so she can take the gas cap off. So she let my car sit for about 3 to 5 mins, its about 20 degrees out, could this play a part in why my hydrocarbons were so high ?

 

Try a new o2 sensor. Make sure the ignition components are fresh. Use stock ecu and set fuel pressure and timing to stock settings.

 

Yeah I'm gonna replace the 02 sensor, the car runs great though, no misfire or anything like that. Here are my other 2 readings even though Illinois does not care about them, they could help. Oh and I know my 02 sensors are not switched around either. I know a lot of people think that could be a problem but I know for a fact there in the right place.

Carbon Dioxide 279.9
NOx 1.30

The parts are pretty new on my car also, well around 1 to 2 years old not to old though.


Modified by 90blackcrx at 4:25 PM 12/13/2004

 

lazy o2 sensor is a somewhat common problem that causes failed emissions.
did you check it with an oscilloscope? if it's not working properly, you'll most likely fail emissions because thats what controls the A/F ratio (i'm sure you know this )

 

Turn down your fuel pressure. It'll help a lot.

Are they doing a dyno test or just the sniffer at idle?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b18-c-rx &raquo;</TD></TR><TR><TD CLASS="quote">lazy o2 sensor is a somewhat common problem that causes failed emissions.
did you check it with an oscilloscope? if it's not working properly, you'll most likely fail emissions because thats what controls the A/F ratio (i'm sure you know this )
</TD></TR></TABLE>

Yeah but I don't have an oscilloscope, I am gonna change the 1 02 sensor that keeps throwing the cel, but should I replace the other one even if it never sets the cel ?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SiRex91 &raquo;</TD></TR><TR><TD CLASS="quote">Turn down your fuel pressure. It'll help a lot.

Are they doing a dyno test or just the sniffer at idle?</TD></TR></TABLE>

How much should I turn it down though ? There putting it on the dyno, which pisses me off because the kid was beating on it and he was more interested in finding out what engine I had. I asked him if he need to know that for the test ( even though I know he didn't ) and he laughed and said no but I figured since you had si rims ( 00 si rims ) that you had an si engine. I told him not to worry about it.

So I'm replacing 1 02 sensor
Changing the oil to get any fuel out
I can turn down the fuel, should I do this at the vafc or fpr ?
Also gonna run the lowest octane

Any other suggestions ?

 

Lower the fuel pressure with the FPR. It helped a friend's built all-motor b18c1 pass IL smog. If you can, put the 17's on the car when you go in for testing so you have a legitimate reason why you don't want your car on the rollers. It will be a lot easier to pass at idle than with them doing WOT on the dyno.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SiRex91 &raquo;</TD></TR><TR><TD CLASS="quote">Lower the fuel pressure with the FPR. It helped a friend's built all-motor b18c1 pass IL smog. If you can, put the 17's on the car when you go in for testing so you have a legitimate reason why you don't want your car on the rollers. It will be a lot easier to pass at idle than with them doing WOT on the dyno.</TD></TR></TABLE>

Ok I'll adjust it a little but how much ? Also I don't have 17's any more.

 

highest octane = guaranteed best combustion possible, which is a plus. I think it's fair to call it a rule of thumb to run the highest octane possible when doing a sniffer test.

try renting an oscilloscope, youll know for sure. but yes, the ecu will not throw a code i believe as long as the o2 unit is functioning - if it's functioning poorly, the ecu can't tell.

as for lowering the fuel pressure, maybe thats not such a good idea, because it might confuse the ecu which is trying to correct the a/f ratio - so it would have adverse effects (but i'm not sure on this one, and if it works, it works)

i'd just set all timing to stock and check sensors.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b18-c-rx &raquo;</TD></TR><TR><TD CLASS="quote">highest octane = guaranteed best combustion possible, which is a plus. I think it's fair to call it a rule of thumb to run the highest octane possible when doing a sniffer test.

try renting an oscilloscope, youll know for sure. but yes, the ecu will not throw a code i believe as long as the o2 unit is functioning - if it's functioning poorly, the ecu can't tell.

as for lowering the fuel pressure, maybe thats not such a good idea, because it might confuse the ecu which is trying to correct the a/f ratio - so it would have adverse effects (but i'm not sure on this one, and if it works, it works)

i'd just set all timing to stock and check sensors.</TD></TR></TABLE>

It would be cheaper just to buy another 02 sensor. Also I'm hearing that the lower the octane rating is, the cleaner the gas will burn. Which makes sense because the lower the octane the sooner it will combust, so all the fuel will combust instead of making its way into the exhaust.


Modified by 90blackcrx at 6:39 PM 12/13/2004

 

Anyone know more about the octane ? I don't have a timing light at the moment so if I just lower the octane can it make the hydrocarbons any worse ?

 

You want the octane as high up as you can.
All it does is provide better combustion.

I'm inclined to agree to a faulty o2 sensor, as well as too high a fuel pressure.

IN the service manual it's described how to test your o2 sensor without an oscillosope, with a regular multimeter.

Those reading are so far off I'm suspecting more than 1 problem.

 

Both 02 sensors are getting replaced.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SETI20 &raquo;</TD></TR><TR><TD CLASS="quote">You want the octane as high up as you can.
All it does is provide better combustion.</TD></TR></TABLE>

Not always, if the temps don't get hot enough its not combust fully. Therefore lowing the octane is gonna result in burning more fuel. Thats how I see it.

 

If the temp's not high enough your mixture is too rich...so you're burning too much anyway, jumping up your emissions.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SETI20 &raquo;</TD></TR><TR><TD CLASS="quote">If the temp's not high enough your mixture is too rich...so you're burning too much anyway, jumping up your emissions.</TD></TR></TABLE>

I agree, but running a higher octane gas, I think would just cause me to burn less fuel. Since the octane rating is really what temp the fuel combust at. So right now if I'm not running hot enough to burn all of the 93 octane, why run higher ?

I also have people telling me to buy this heat stuff, but I see that increasing octane to so I'm a little confused.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 90blackcrx &raquo;</TD></TR><TR><TD CLASS="quote">... is really what temp the fuel combust at. </TD></TR></TABLE>

Incorrect. The octane rating is the ability to resist premature combustion thus makin git more stable. That does not mean it burns at a different temperature. That would be BAD news for race cars.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SETI20 &raquo;</TD></TR><TR><TD CLASS="quote">
Incorrect. The octane rating is the ability to resist premature combustion thus makin git more stable. That does not mean it burns at a different temperature. That would be BAD news for race cars.</TD></TR></TABLE>

Ok but if it was lower wouldn't more exploded in the cylinder ?

 

the chemical properties of higher octane gas makes it avoid premature combustion, which is the only issue here. I do believe that it's safe to say a rule of thumb for smogging is run the highest octane possible.

you have two o2 sensors? obd2 compliant or what?

 

Advanced ignition timing will increase HC's(unburned fuel) as well. Here is a list of things in order that I would check:
-ign components(good spark is needed for proper combustion)
-fuel system(make sure fuel pressure is at stock setting and that all o2 sensors are functioning.
-no vacuum leaks(obvious to find)
-alot of times like in my case my B16 would of passed the im240 easily if the catco cat wasnt bad.
Just a little FYI on o2 sensors. Checking their function is easy. Grab a multimeter and unplug the harness. Grab the connector from the o2 sensor side and connect your meter to it. Your meter will have to be on mV in order to read the low voltage. It should jump between 100mV to 900mV or so. It should do this at least 20 or so times in 30 secs. If not its slow and needs replacing. HTH

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b18-c-rx &raquo;</TD></TR><TR><TD CLASS="quote">the chemical properties of higher octane gas makes it avoid premature combustion, which is the only issue here. I do believe that it's safe to say a rule of thumb for smogging is run the highest octane possible.

you have two o2 sensors? obd2 compliant or what?</TD></TR></TABLE>

I am running obd0

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Cory man &raquo;</TD></TR><TR><TD CLASS="quote">Advanced ignition timing will increase HC's(unburned fuel) as well. Here is a list of things in order that I would check:
-ign components(good spark is needed for proper combustion)
-fuel system(make sure fuel pressure is at stock setting and that all o2 sensors are functioning.
-no vacuum leaks(obvious to find)
-alot of times like in my case my B16 would of passed the im240 easily if the catco cat wasnt bad.
Just a little FYI on o2 sensors. Checking their function is easy. Grab a multimeter and unplug the harness. Grab the connector from the o2 sensor side and connect your meter to it. Your meter will have to be on mV in order to read the low voltage. It should jump between 100mV to 900mV or so. It should do this at least 20 or so times in 30 secs. If not its slow and needs replacing. HTH</TD></TR></TABLE>

The 02 sensors are gonna be brand new so rule out that from now on. I know I have no vacuum leaks. The cat is brand new, well I took it from a friend that just passed emissions. I will check timing soon.

When I went to school my teacher always told me to use Tyrolean ( sp ) , basically its a paint thinner. Can anyone see how this would work, does it burn cleaner ? See I still am not 100% for sure that the higher octane is the smart thing to do when going to the emissions. I'm hearing conflicting things.

Also does anyone know for sure the stock vtec cross over for the pr3 and pw0 computer. People say so many different things, I'm hearing its 4,800 but I really think its 5,300

 

I once heard if you mist plain water in your intake it may help with emission readings. Anyway Bump for a topic I want to know more about

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mightyt11 &raquo;</TD></TR><TR><TD CLASS="quote">I once heard if you mist plain water in your intake it may help with emission readings. Anyway Bump for a topic I want to know more about</TD></TR></TABLE>

Yeah someone I know suggested that to

By the way in Illinois NOx is not something we need to pass, so keeping that in mind, should I just lean my car out ? I know in some states you have to watch out how far you lean your car out because the leaning you run, the more NOx goes up.

 

Been reading a little and it seems like the secret weapon might be

denatured alcohol

Any comments on that stuff ?

 

90blackcrx : My understanding of octane is the same as yours. I guess we need to do more research.

Anyways, i smogged motors caling for 91 with 89 and it had no adverse affects on the emissions that i could tell. They passed everytime. It seems that if it did make a difference, it would only be slightly, and its not enough for what u need. U have a bigger problem and need to find it. Changing the O2's is a good step. Also, make sure they arent switched around.

 

I have the hasport wiring kit so switching them around is pretty much impossible.