smog check and "check engine soon" light

Hey Everyone, my '93 SL2 just failed a smog check today (Los Angeles).
Why? The "Check Engine Soon" light came on while the tester was revving
the engine. He said this means I failed the "System Malfunction Light"
test on the sheet (passed everything else). Is this accurate? I'm just
used to ignoring the light, since it doesn't seem to indicate anything
except that I'm driving faster than 60 mph. By the way, what does the
"Check Engine Soon" light have to do with emmisions? Or does it indicate
that something *might* be wrong with the emissions? By the way, I get a
free re-test. Thanks!

Meph

 

Mine came on when the EGR valve was malfunctioning. Simple fix was to
remove the EGR (5 minutes job) and clean all the carbon deposits out (10
Minutes), lubricate and reinstall. Pretty simple. I believe that the OBD
code was 032, although this may not be correct since it is from memory.

Bob

 

Ahh yes, my car failed the test two years ago, and the mechanic cleaned
something and it retested fine. I need to check the paperwork to see if
it was the EGR valve, which sounds kinda familiar. Thanks man!

So... I have ten days to do the free retest. If you were I, would you
just clean the EGR valve, roll the dice and get the retest, or would you
pay to have a mechanic look at it before the retest? Or are there
places in Los Angeles that will run the codes for a reasonable price?

My spark plugs are new, but the wires are old, so maybe I should just
replace these like Jonnie mentioned.

Thanks again, guys!

Meph

 

What is the code causing the "Check Engine Soon" light to come on?
Some parts stores will check the code for free.
Knowing the code should help fix it.

 

The EGR gasket cost $3 and the part is easily accessible. There are only
two bolts and an electrical plug to remove. The hardest part of the job was
scraping off the old gasket (I used a rotary wire brush on a battery powered
drill). I used a small screwdriver to scrape inside the valve body and
there was a considerable amount of carbon that came out. The whole job took
about 20 minutes max. What do you have to lose?

Bob

 

Still 900 times more than the paperclip that worked before OBDII.

Joy. How do you even KNOW it's gone through a 'cycle'?

This begs the question - if ODBII is that useful (and I doubt it is),
why even BOTHER with the treadmill testing? If the treadmill testing
reflects actual driving, why bother checking the ODBII light?

CT dumped their testing program after enough people complained about the
process (going to the state contracted center, waiting 45 min on line,
paying a lot, possibly failing, finding a specially licensed mechanic,
getting the repairs, repeating...), and about their cars getting trashed
(which the state/contractor/EPA somehow thinks is the owner's fault,
naturally), and about the general system.

Could be worse, the drive by type sensors advocated in some circles are
uselessly inaccurate, even according to the manufacturer's own data.

NJ just implemented a new rule - 5 years between tests on any car made
after 2000. NY still insists you get a test every freaking year. The
sad thing being, there's not much proof this stuff works, it's just that
states do it because the EPA basically blackmails them into it.

 

They're going for $100 on Ebay, so I can see myself buying one and selling
it on Ebay when I'm done. I don't know anything about this stuff, but
when I did a Google search, it said OBDII was for cars from 1996 onward.
My car is a 1993 SL2. Does this mean I can read the codes without any
special tools? If so, could someone describe how? Haven't found it in
the Chilton or Haynes manuals.

What is "I/M 250"?

Actually according to the test, my nitric oxide level at 15 mph is
borderline (703 measured, 720 max, but 150 is average) so I will take
measures to get this down, since this is what I think the test should be
about-- not some stupid light coming on. However, I got a reading of 335
at 25 mph (avergae 136, max 774) so it seems the margin of error for the
testing equipment may be ridiculously high, unfortunately.

Interesting story: my sister got a new Accord last year, and the "check
engine" light always came on in her car. Solution? The dealer told her
how to disable it. Fortunately new cars don't have to take smog tests (and
she isn't in a smog test state)

So, the all the triggered problem codes are stored in the computer until
you read them? I didn't understand this before.

I called the DMV today, and they give financial aid to broke people who
have to get repairs to pass a smog check, up to $500. I'm broke enough to
qualify, but since they tell you where to get your car fixed, and the
mechanic knows how much they're willing to reimburse, I'd be surprised if
my "repairs" cost less than $500. They also let you get a temporary
registration if the deadline passes and you still haven't passed the smog
test.

The tester took my gas cap off and inspected it, and this is part of the
test. It's kind of depressing that your car has to be in tip top shape
every two years, given that having a car here is essentially a
requirement, along with liability insurance and $2.20 per gallon gas.
Those who want seriously better public transportation here are dismissed
as pinko commies.

Thanks for all the help, and reading my rants!

Meph

 

To your comment and question, the great state of Illinois, where I live, no
longer does the treadmill testing if the vehicle is equipped with OBDII and
the vehicle's computer shows it is in good running condition. The only test
they do is to connect the OBDII cable and toggle the SES light to make sure
it was not disabled by the owner (as you had suggested).

On older vehicles, they still connect the computer and do the full
dynamometer test.

Bob

 

Yes! the code is 32. I just went to AutoZone. My car is not an OBDII. I
bought a thingy that is essentially a glorified jumper, for $2, and they
showed me how to use it (Isn't that AWESOME!!!! Just $2 to read the
codes!!!). They even showed me the page in my Haynes manual where the
codes are! You stick the jumper in, and the "check engine soon" light flashes
repeatedly to indicate the tens and ones digits of the codes. Cool as
hell. Anyway, I got codes 26 (Quad driver output fault) and 32 (EGR
system fault). Now I'm definitely not taking this to a mechanic.

Thanks all!

Meph

 

I know that some areas, when testing OBD II vehicles, will hook up a scanner
and check the readiness flags for the various diagnostics that need special
conditions in order to run (catalyst monitor, evaporative system, etc.) If
any of them show up as "not ready", indicating the test hasn't been run
since the system was reset, they tell the owner to bring it back later for a
test after it has been driven for a while and the test has had a chance to
run. This prevents people who have the Check Engine light on all the time
from just clearing the code and immediately going for an inspection before
it has a chance to run the diagnostic and turn the light back on.

Apparently the NCVECS folks (http://www.obdiicsu.com/) have found, from the
vehicles that people have brought in to them to fix as part of the research
they do, that it's rare for OBD II vehicles to have high emissions but not
have the Check Engine light on. Therefore, it would seem that dispensing
with the tailpipe test for OBD II vehicles would be a sensible thing to do
budget-wise..

 

Have fun convincing the EPA of that. I/M 240 at least makes it look
like something's being done, even though the value of it is suspect.
not to mention, most mechanics around here hate the machines - they're
unreliable, very expensive, and dangerous - one locked up at a shop near
me and sent the car through a wall. The EPA will tell you that this
stuff is safe, but anyone could tell you that sticking a car on a dyno
is at best a risky proceedure...