Honda Car Forum

i have a 93 civic lx (engine = D15B7) that was not manufactured with
an EGR valve, which is weird to me cause i thought all modern
vehicles had one (since the late 70's). I failed california smog 4
times with twice the legal limits of NOX but everything else was fine,
i'm assuming the catalytic converter is the only thing that fixes this
right, as it is likely a 3-way cat?

also does anyone know is using a PCV catch can (oil catch can) is smog
legal in california? i know they are sticklers when it comes to
anything emissions related, as most things need to have a CARB
approved # stamped on them, but since the catch can only catches the
oil and does not stop the air from recirculating and burning up as
intended i dont see why it would be illegal, lowers emissions right?

i know high nox is due to high combustion chamber temps, besides
de-carbonizing the piston tops what else would lower nox on a non egr
vehicle?

vairox <nothere@spammasters.com> wrote in
news:81cl429vgo5ejvaen1sd9dcegi3imdgaa1@4ax.com:

> i have a 93 civic lx (engine = D15B7) that was not manufactured with
> an EGR valve, which is weird to me cause i thought all modern
> vehicles had one (since the late 70's). I failed california smog 4
> times with twice the legal limits of NOX but everything else was fine,
> i'm assuming the catalytic converter is the only thing that fixes this
> right, as it is likely a 3-way cat?

maybe a bad O2 sensor? any codes set on the ECU?
>
> also does anyone know is using a PCV catch can (oil catch can) is smog
> legal in california? i know they are sticklers when it comes to
> anything emissions related, as most things need to have a CARB
> approved # stamped on them, but since the catch can only catches the
> oil and does not stop the air from recirculating and burning up as
> intended i dont see why it would be illegal, lowers emissions right?
>
> i know high nox is due to high combustion chamber temps, besides
> de-carbonizing the piston tops what else would lower nox on a non egr
> vehicle?
>



--
Jim Yanik
jyanik
at
kua.net

"vairox" <nothere@spammasters.com> wrote in message
news:81cl429vgo5ejvaen1sd9dcegi3imdgaa1@4ax.com...
>i have a 93 civic lx (engine = D15B7) that was not manufactured with
> an EGR valve, which is weird to me cause i thought all modern
> vehicles had one (since the late 70's). I failed california smog 4
> times with twice the legal limits of NOX but everything else was fine,
> i'm assuming the catalytic converter is the only thing that fixes this
> right, as it is likely a 3-way cat?
>
> also does anyone know is using a PCV catch can (oil catch can) is smog
> legal in california? i know they are sticklers when it comes to
> anything emissions related, as most things need to have a CARB
> approved # stamped on them, but since the catch can only catches the
> oil and does not stop the air from recirculating and burning up as
> intended i dont see why it would be illegal, lowers emissions right?
>
> i know high nox is due to high combustion chamber temps, besides
> de-carbonizing the piston tops what else would lower nox on a non egr
> vehicle?

That's about the size of it - the NOx stage of the cat is bad... assuming it
is a 3-stage cat. The absence of EGR makes me think that is so.

Make sure the timing is correct. Advanced timing will raise the NOx level,
but AFAIK a 3-stage catalytic converter hides that as long as it is working.

Mike

thanks guys... the O2 sensor was replaced by a shop the last time it
failed (in july 04) and it failed with harder NOX and a higher amount
of HC, though it was still in the legal limit....

no ECU codes...

might install a magnaflow direct fit replacement, if i can get them to
confirm it is california smog/noise legal...

sort of stumped cause i have another inspection coming up in june or
july.... i am now using the proper OEM NGK plugs, did some intake
cleaner throught the booster, idles much better, drives smoother...
cleaned a lot of carbon off the pistons.

you guys know what effect a PCV catch can would have on emissions? i
know it wouldnt do squat on NOX, thats temp related....but any others?

You're correct: A 93 Civic LX does not have an EGR system,
according to my Chilton's.

This seems like a helpful site:
http://www.aircare.ca/index.php?repinfo-glossary.php . See
especially
"Causes of Excess Emissions."

It puts a lot of emphasis on an improperly functioning EGR
system causing
high NOx , but it lists a few other causes, too. None are
the PCV valve.

http://www.interro.com/techgas.html#anchoreleven states
similar.

An improperly functioning PCV valve may cause high CO, which
you don't have.

What is a PCV valve "catch can"? Did you remove the PCV
valve?

"vairox" <nothere@spammasters.com> wrote
> thanks guys... the O2 sensor was replaced by a shop the
> last time it
> failed (in july 04) and it failed with harder NOX and a
> higher amount
> of HC, though it was still in the legal limit....
>
> no ECU codes...
>
> might install a magnaflow direct fit replacement, if i can
> get them to
> confirm it is california smog/noise legal...
>
> sort of stumped cause i have another inspection coming up
> in june or
> july.... i am now using the proper OEM NGK plugs, did some
> intake
> cleaner throught the booster, idles much better, drives
> smoother...
> cleaned a lot of carbon off the pistons.
>
> you guys know what effect a PCV catch can would have on
> emissions? i
> know it wouldnt do squat on NOX, thats temp related....but
> any others?
>
>

On Sun, 23 Apr 2006 13:33:47 GMT, "Elle"
<honda.lioness@nospam.earthlink.net> wrote:

>You're correct: A 93 Civic LX does not have an EGR system,
>according to my Chilton's.
>
>This seems like a helpful site:
>http://www.aircare.ca/index.php?repinfo-glossary.php . See
>especially
>"Causes of Excess Emissions."
>
>It puts a lot of emphasis on an improperly functioning EGR
>system causing
>high NOx , but it lists a few other causes, too. None are
>the PCV valve.
>
>http://www.interro.com/techgas.html#anchoreleven states
>similar.
>
>An improperly functioning PCV valve may cause high CO, which
>you don't have.
>
>What is a PCV valve "catch can"? Did you remove the PCV
>valve?
>
>"vairox" <nothere@spammasters.com> wrote
>> thanks guys... the O2 sensor was replaced by a shop the
>> last time it
>> failed (in july 04) and it failed with harder NOX and a
>> higher amount
>> of HC, though it was still in the legal limit....
>>
>> no ECU codes...
>>
>> might install a magnaflow direct fit replacement, if i can
>> get them to
>> confirm it is california smog/noise legal...
>>
>> sort of stumped cause i have another inspection coming up
>> in june or
>> july.... i am now using the proper OEM NGK plugs, did some
>> intake
>> cleaner throught the booster, idles much better, drives
>> smoother...
>> cleaned a lot of carbon off the pistons.
>>
>> you guys know what effect a PCV catch can would have on
>> emissions? i
>> know it wouldnt do squat on NOX, thats temp related....but
>> any others?
>>
>>
>

thanks for checking the chiltons, i only have a haynes and it's not
very specific about that... PCV catch can is just a can more or less,
you take the hose that comes off the PCV valve and it connects to a
can, then another hose goes from the other side of the can and goes
back to where the PCV hose originally went, it just sits in-line of
the PCV hose to catch all the oil blowby so it doesnt gum up the
intake/valves etc... still allows the gasses to go by and get burned
up...

what are the other causes of high nox? high combustion chamber temps
due to carbon buildup is one but im not sure of any others

In article <kfkn42tvaipokjplcnm1arlpqt85j3rehc@4ax.com>, vairox
<nothere@spammasters.com> wrote:

> On Sun, 23 Apr 2006 13:33:47 GMT, "Elle"
> <honda.lioness@nospam.earthlink.net> wrote:
>
> >You're correct: A 93 Civic LX does not have an EGR system,
> >according to my Chilton's.
> >
> >This seems like a helpful site:
> >http://www.aircare.ca/index.php?repinfo-glossary.php . See
> >especially
> >"Causes of Excess Emissions."
> >
> >It puts a lot of emphasis on an improperly functioning EGR
> >system causing
> >high NOx , but it lists a few other causes, too. None are
> >the PCV valve.
> >
> >http://www.interro.com/techgas.html#anchoreleven states
> >similar.
> >
> >An improperly functioning PCV valve may cause high CO, which
> >you don't have.
> >
> >What is a PCV valve "catch can"? Did you remove the PCV
> >valve?
> >
> >"vairox" <nothere@spammasters.com> wrote
> >> thanks guys... the O2 sensor was replaced by a shop the
> >> last time it
> >> failed (in july 04) and it failed with harder NOX and a
> >> higher amount
> >> of HC, though it was still in the legal limit....
> >>
> >> no ECU codes...
> >>
> >> might install a magnaflow direct fit replacement, if i can
> >> get them to
> >> confirm it is california smog/noise legal...
> >>
> >> sort of stumped cause i have another inspection coming up
> >> in june or
> >> july.... i am now using the proper OEM NGK plugs, did some
> >> intake
> >> cleaner throught the booster, idles much better, drives
> >> smoother...
> >> cleaned a lot of carbon off the pistons.
> >>
> >> you guys know what effect a PCV catch can would have on
> >> emissions? i
> >> know it wouldnt do squat on NOX, thats temp related....but
> >> any others?
> >>
> >>
> >
>
> thanks for checking the chiltons, i only have a haynes and it's not
> very specific about that... PCV catch can is just a can more or less,
> you take the hose that comes off the PCV valve and it connects to a
> can, then another hose goes from the other side of the can and goes
> back to where the PCV hose originally went, it just sits in-line of
> the PCV hose to catch all the oil blowby so it doesnt gum up the
> intake/valves etc... still allows the gasses to go by and get burned
> up...
>
> what are the other causes of high nox? high combustion chamber temps
> due to carbon buildup is one but im not sure of any others

I can only guess:
defective rings
defective muffler
defective cat. coverter
valves not adjusted correctly
timing set incorrectly
defective plugs or plugs not gapped correctly

If you hook the engine up to a computerized engine tester--it should
discover the source of the problem. I show a recent post where someone
replaced all of the parts of his engine that might have caused his engine
to stall on a regular basis. It makes more sense to use testing equipment
to discover the exact cause of a problem instead of replacing a bunch of
parts that are working great.
Jason

--
NEWSGROUP SUBSCRIBERS MOTTO
We respect those subscribers that ask for advice or provide advice.
We do NOT respect the subscribers that enjoy criticizing people.

"vairox" <nothere@spammasters.com> wrote in message
news:kfkn42tvaipokjplcnm1arlpqt85j3rehc@4ax.com...
> On Sun, 23 Apr 2006 13:33:47 GMT, "Elle"
> <honda.lioness@nospam.earthlink.net> wrote:
>
>
> what are the other causes of high nox? high combustion chamber temps
> due to carbon buildup is one but im not sure of any others
>
Technically, the causes are high temperatures and rapid cooling, which
causes the NOx to "freeze" instead of decaying as the gases cooled.

Since the expansion time is pretty much determined by engine speed, that
leaves combustion temperature as the factor we can control. Carbon really
isn't an issue directly, but it can cause preignition which has the same
effect as advanced ignition timing. The two big culprits are ignition timing
and mixture. Advanced timing increases combustion temperatures, and a leaner
mixture at high throttle settings (when it should be rich anyway to
forestall detonation) does the same. EGR reduces the temperature by diluting
the mixture without affecting the air/fuel ratio.

Mike

Michael Pardee wrote:
> "vairox" <nothere@spammasters.com> wrote in message
> news:kfkn42tvaipokjplcnm1arlpqt85j3rehc@4ax.com...
>
>>On Sun, 23 Apr 2006 13:33:47 GMT, "Elle"
>><honda.lioness@nospam.earthlink.net> wrote:
>>
>>
>>what are the other causes of high nox? high combustion chamber temps
>>due to carbon buildup is one but im not sure of any others
>>
>
> Technically, the causes are high temperatures and rapid cooling, which
> causes the NOx to "freeze" instead of decaying as the gases cooled.
>
> Since the expansion time is pretty much determined by engine speed, that
> leaves combustion temperature as the factor we can control. Carbon really
> isn't an issue directly, but it can cause preignition which has the same
> effect as advanced ignition timing. The two big culprits are ignition timing
> and mixture. Advanced timing increases combustion temperatures, and a leaner
> mixture at high throttle settings (when it should be rich anyway to
> forestall detonation) does the same. EGR reduces the temperature by diluting
> the mixture without affecting the air/fuel ratio.
>
> Mike
>
>

good post. yes, check timing and mixture. mixture can be assisted by
running a couple of tanks with injector cleaner through the vehicle.
timing should be set with the maintenance jumper connected. and it
should be dead-on, not just close. regarding egr, it's often addressed
these days by increasing the overlap between exhaust and inlet valve
timing, so make sure the valve clearances are correct.

to the op, no, an oil catch can is illegal in california.

On Sun, 23 Apr 2006 13:26:43 -0700, jim beam <nospam@example.net>
wrote:

>Michael Pardee wrote:
>> "vairox" <nothere@spammasters.com> wrote in message
>> news:kfkn42tvaipokjplcnm1arlpqt85j3rehc@4ax.com...
>>
>>>On Sun, 23 Apr 2006 13:33:47 GMT, "Elle"
>>><honda.lioness@nospam.earthlink.net> wrote:
>>>
>>>
>>>what are the other causes of high nox? high combustion chamber temps
>>>due to carbon buildup is one but im not sure of any others
>>>
>>
>> Technically, the causes are high temperatures and rapid cooling, which
>> causes the NOx to "freeze" instead of decaying as the gases cooled.
>>
>> Since the expansion time is pretty much determined by engine speed, that
>> leaves combustion temperature as the factor we can control. Carbon really
>> isn't an issue directly, but it can cause preignition which has the same
>> effect as advanced ignition timing. The two big culprits are ignition timing
>> and mixture. Advanced timing increases combustion temperatures, and a leaner
>> mixture at high throttle settings (when it should be rich anyway to
>> forestall detonation) does the same. EGR reduces the temperature by diluting
>> the mixture without affecting the air/fuel ratio.
>>
>> Mike
>>
>>
>
>good post. yes, check timing and mixture. mixture can be assisted by
>running a couple of tanks with injector cleaner through the vehicle.
>timing should be set with the maintenance jumper connected. and it
>should be dead-on, not just close. regarding egr, it's often addressed
>these days by increasing the overlap between exhaust and inlet valve
>timing, so make sure the valve clearances are correct.
>
>to the op, no, an oil catch can is illegal in california.


why is a catch can illegal?

good advice guys, someone from another newsgroup claims that the car
DOES use an EGR and said to go to

http://www.smpcorp.com/web_app/catalog/publicweb_bg.asp

then put in part # EGV551


i can see a mount near the valve cover where one WOULD go, but i think
the only cars of this era that had one are the ex and vx ?

may have to adjust the valves, it's pretty tough to get the timing
dead on considering the rpm's go up when the fan kicks on to cool the
engine, and finding 650rpm's EXACTLY on the tach is just a guess.