Darn! My '94 Del Sol failed the California Smog Check today

After having passed the California smog check for 2 tests (4 years) in a
row, my stock '94 Del Sol ("S" model with 1.5L engine) failed today. :-(
It's the first time I've ever had any car fail the Smog Check, in 20 years
of living in California.

I have never made any modifications to the engine, and I take it in for
regular maintenance according to the maintenance schedule. It has been
about 6500 miles since its last oil change, and I don't use any pour-in fuel
additives. It is running normally with no noticeable engine problems.

Here in California the DMV has recently made the Smog Check test more
sophisticated, using a 'dynamometer' (treadmill) to test the car under load.
They test the car at a simulated 15mph and at 25mph. They also added a NOX
(nitrous oxide) emissions check, and that's the one that my car failed, but
only at 15mph.

As for my other emissions test results, my Del Sol had extremely low CO2,
O2, HC and CO emissions at both 15mph and 25mph, but failed the Nitrous
Oxide (NOX) test at 15mph. In fact, the NOX emission was about 3 times
higher at 15mph than at 25mph, which seems counter-intuitive. I had driven
the car at least 15 miles before arriving at the test facility, so it was
well warmed-up.

Has anyone else seen this kind of failure with an older Honda Civic or Del
Sol? If so, what was the culprit? I'm trying to get an idea how much it's
going to cost to have it fixed.

Thanks for any ideas, feedback, or sympathy. :-)

-DK

DavidK wrote:
> After having passed the California smog check for 2 tests (4 years) in a
> row, my stock '94 Del Sol ("S" model with 1.5L engine) failed today. :-(
> It's the first time I've ever had any car fail the Smog Check, in 20 years
> of living in California.
>
> I have never made any modifications to the engine, and I take it in for
> regular maintenance according to the maintenance schedule. It has been
> about 6500 miles since its last oil change, and I don't use any pour-in fuel
> additives. It is running normally with no noticeable engine problems.
>
> Here in California the DMV has recently made the Smog Check test more
> sophisticated, using a 'dynamometer' (treadmill) to test the car under load.
> They test the car at a simulated 15mph and at 25mph. They also added a NOX
> (nitrous oxide) emissions check, and that's the one that my car failed, but
> only at 15mph.
>

NOX is usually a function of the EGR valve, which your car might not
have. timing can also effect it, so id check that and replace the
plugs/plug wires/dist cap/rotor with OEM if necessary.

went through all that with a 1975 MG midget. by the time i got the EGR
unclogged, the smog pump working right, and a new $99 catalytic
converter on, it passed with flying colors. IIRC, some of the emissions
were *0*.

> As for my other emissions test results, my Del Sol had extremely low CO2,
> O2, HC and CO emissions at both 15mph and 25mph, but failed the Nitrous
> Oxide (NOX) test at 15mph. In fact, the NOX emission was about 3 times
> higher at 15mph than at 25mph, which seems counter-intuitive. I had driven
> the car at least 15 miles before arriving at the test facility, so it was
> well warmed-up.
>
> Has anyone else seen this kind of failure with an older Honda Civic or Del
> Sol? If so, what was the culprit? I'm trying to get an idea how much it's
> going to cost to have it fixed.

the O2 sensor is likely long overdue, if its never been replaced. a
place that ISNT "test only" should be able to pinpoint the exact problem.
>
> Thanks for any ideas, feedback, or sympathy. :-)
>
> -DK
>

"DavidK" > wrote in
. com:

> After having passed the California smog check for 2 tests (4 years) in
> a row, my stock '94 Del Sol ("S" model with 1.5L engine) failed today.
> :-( It's the first time I've ever had any car fail the Smog Check, in
> 20 years of living in California.



Post ALL your numbers, including the limits for your area.



>
> I have never made any modifications to the engine, and I take it in
> for regular maintenance according to the maintenance schedule. It has
> been about 6500 miles since its last oil change, and I don't use any
> pour-in fuel additives. It is running normally with no noticeable
> engine problems.
>
> Here in California the DMV has recently made the Smog Check test more
> sophisticated, using a 'dynamometer' (treadmill) to test the car under
> load. They test the car at a simulated 15mph and at 25mph. They also
> added a NOX (nitrous oxide) emissions check, and that's the one that
> my car failed, but only at 15mph.



Post ALL your numbers, including the limits for your area.



>
> As for my other emissions test results, my Del Sol had extremely low
> CO2, O2, HC and CO emissions at both 15mph and 25mph, but failed the
> Nitrous Oxide (NOX) test at 15mph. In fact, the NOX emission was
> about 3 times higher at 15mph than at 25mph, which seems
> counter-intuitive. I had driven the car at least 15 miles before
> arriving at the test facility, so it was well warmed-up.



Post ALL your numbers, including the limits for your area.

If you were extremely low in HC and CO, that suggests either you're running
hot, timing is too far advanced, or your EGR system is not working
correctly.

You cannot be extremely low in CO2 if you were extremely low in HC and CO.
If you were very low in HC and CO, that means the cat has managed to bind
its stored oxygen to the CO and HCs to make them into CO2 and water. So CO2
ought to be HIGH.


--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

"TeGGeR®" > wrote in
:


>
> If you were extremely low in HC and CO,



AND your NOx numbers are high, I meant to say...



> that suggests either you're
> running hot, timing is too far advanced, or your EGR system is not
> working correctly.

--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

Hello and thanks for all the responses. Here are all of the Emmission Test
Result numbers from my failing test report:

= = = = = = = = = = = = = = =

Line 1:

Test=15mph
RPM=1727
%CO2 meas=15.6
%02 meas=0.0
HC (PPM) MAX=92, AVE=21, MEAS=13
CO (%) MAX=0.55, AVE=0.06, MEAS=0.03
NO (PPM) MAX=716, AVE=150, MEAS=991
FAIL
= = = = = = = = = = = = = = =

Line 2:

RPM=1904
%CO2 meas=15.5
%02 meas=0.0
HC (PPM) MAX=57, AVE=13, MEAS=11
CO (%) MAX=0.54, AVE=0.05, MEAS=0.02
NO (PPM) MAX=764, AVE=136, MEAS=354
PASS
= = = = = = = = = = = = = = =

-DK


"DavidK" > wrote in message
. com...
> After having passed the California smog check for 2 tests (4 years) in a
> row, my stock '94 Del Sol ("S" model with 1.5L engine) failed today. :-(
> It's the first time I've ever had any car fail the Smog Check, in 20 years
> of living in California.
>
> I have never made any modifications to the engine, and I take it in for
> regular maintenance according to the maintenance schedule. It has been
> about 6500 miles since its last oil change, and I don't use any pour-in
fuel
> additives. It is running normally with no noticeable engine problems.
>
> Here in California the DMV has recently made the Smog Check test more
> sophisticated, using a 'dynamometer' (treadmill) to test the car under
load.
> They test the car at a simulated 15mph and at 25mph. They also added a
NOX
> (nitrous oxide) emissions check, and that's the one that my car failed,
but
> only at 15mph.
>
> As for my other emissions test results, my Del Sol had extremely low CO2,
> O2, HC and CO emissions at both 15mph and 25mph, but failed the Nitrous
> Oxide (NOX) test at 15mph. In fact, the NOX emission was about 3 times
> higher at 15mph than at 25mph, which seems counter-intuitive. I had
driven
> the car at least 15 miles before arriving at the test facility, so it was
> well warmed-up.
>
> Has anyone else seen this kind of failure with an older Honda Civic or Del
> Sol? If so, what was the culprit? I'm trying to get an idea how much
it's
> going to cost to have it fixed.
>
> Thanks for any ideas, feedback, or sympathy. :-)
>
> -DK
>

For the Line 2 numbers, I forgot to type "Test = 25mph".

-DK

"DavidK" > wrote in
om:

> Hello and thanks for all the responses. Here are all of the
> Emmission Test Result numbers from my failing test report:
>
> = = = = = = = = = = = = = = =
>
> Line 1:
>
> Test=15mph
> RPM=1727
> %CO2 meas=15.6


Good number there. Means the catalytic converter is successfully converting
the CO into CO2.


> %02 meas=0.0


Good. Means the cat is soaking up oxygen properly, so it's in good shape.
It also suggests you don't have an exhaust leak.


> HC (PPM) MAX=92, AVE=21, MEAS=13


Low number there. You're probably running lean.


> CO (%) MAX=0.55, AVE=0.06, MEAS=0.03


You're running a bit lean.


> NO (PPM) MAX=716, AVE=150, MEAS=991


California checks your ignition timing as part of the test, doesn't it?
Then we can rule that out.

Possible causes:
EGR passage to the EGR valve carboned up
Fuel pressure regulator weak
Rich-biased oxygen sensor

I'd run a bottle or two of Techron through it for the next week or so (just
to make sure the injectors and valve tops are reasonably clean) and then
take it back for a retest. If it still fails on the same thing, clean the
EGR passages.


--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

TeGGeR® wrote:
> California checks your ignition timing as part of the test, doesn't it?

theyre *supposed* to. whether the mechanic can read the marks correctly
is another story. and if it was done at a "test only" station, they
arent allowed to fix it, and arent even supposed to suggest a cause.

> Then we can rule that out.
>
> Possible causes:
> EGR passage to the EGR valve carboned up

on my MG, the actual EGR valve was faulty. i applied vacuum to it with a
mityvac hand pump, or TRIED to. wouldnt work. took it off and inspected,
the diaphragm was split.

> Fuel pressure regulator weak
> Rich-biased oxygen sensor
>
> I'd run a bottle or two of Techron through it for the next week or so (just
> to make sure the injectors and valve tops are reasonably clean) and then
> take it back for a retest. If it still fails on the same thing, clean the
> EGR passages.

id vote for the timing being off.

Does a del sol have an EGR? My 98 civic 1.6 SOHC Non Vtec does not.

SoCalMike wrote:
>> California checks your ignition timing as part of the test, doesn't it?
>
>theyre *supposed* to. whether the mechanic can read the marks correctly
>is another story. and if it was done at a "test only" station, they
>arent allowed to fix it, and arent even supposed to suggest a cause.
>
>> Then we can rule that out.
>>
>> Possible causes:
>> EGR passage to the EGR valve carboned up
>
>on my MG, the actual EGR valve was faulty. i applied vacuum to it with a
>mityvac hand pump, or TRIED to. wouldnt work. took it off and inspected,
>the diaphragm was split.
>
>> Fuel pressure regulator weak
>> Rich-biased oxygen sensor
>[quoted text clipped - 3 lines]
>> take it back for a retest. If it still fails on the same thing, clean the
>> EGR passages.
>
>id vote for the timing being off.

--
Message posted via CarKB.com
http://www.carkb.com/Uwe/Forums.aspx...-cars/200601/1

T L via CarKB.com wrote:
> Does a del sol have an EGR? My 98 civic 1.6 SOHC Non Vtec does not.

thats what i was wondering too. i dont think they do, which would mean
some kind of timing problem, at low speed. too retarded? advanced? is
there a vacuum thingie on the distributor?