Need help interpreting CA smog test results

I just passed my smog test, but just barely.. I have both the new and
old numbers (recent test, and test from 1.5 years ago). Wondering if
anyone can tell me if I have a developing car problem I can fix before
it gets bad.. I was targeted as a "High Profile Emitter" and forced
to go to a test only center. Preparations listed below..

Note the HC, I barely made it.


Auto: 1996 Honda Prelude, VTEC H22A
Test: June 2004
CO2 O2
Test RPM MEAS MEAS
15mph 1802 14.9 0.0
25mph 2106 14.9 0.0

HC
Test RPM MAX AVG MEAS
15mph 1802 58 9 56
25mph 2106 42 7 38


CO
Test RPM MAX AVG MEAS
15mph 1802 0.52 0.02 0.08
25mph 2106 0.50 0.03 0.05


NO
Test RPM MAX AVG MEAS
15mph 1802 451 57 204
25mph 2106 738 50 139



For the test itself, I changed the PCV, Air Filter, Changed the oil
and oil filter, put in a full tank of 91 octane gas (actually, my car
takes 91 octane, so that's what I normally use).. I also drove it on
the freeway for 30+ miles (45 mins) and then brought it in.. I was
forced to wait, but I went and topped off my tank instead of waiting,
and then sat in traffic, which hopefully kept the car hot..

I didn't put any additives in to clean the injectors, which is
something I wish I had done..

I also changed the plugs about a year ago, they are the expensive 60k
mile plugs, and I only put 15,000 on them...

I also may need a valve adjustment (or have them checked).. I don't
know if that would throw it off much, I hope to do it myself, but
haven't had the time. I don't think they are out of specs though..

The original owner (I bought it 1.5 years ago) brought it to the
dealership regularly and had all the records. He seemed to take good
care of it, and the title xfer smog test kinda indicated that, plus I
don't think he warmed the car up enough for his test..

Here is the Original change of title Test that I got with the car.

Test Date: Jan 2003


CO2 O2
Test RPM MEAS MEAS
15mph 1946 14.9 0.0
25mph 2200 14.9 0.0

HC
Test RPM MAX AVG MEAS
15mph 1946 58 9 19
25mph 2200 42 7 15


CO
Test RPM MAX AVG MEAS
15mph 1946 0.52 0.02 0.01
25mph 2200 0.50 0.02 0.01


NO
Test RPM MAX AVG MEAS
15mph 1946 804 66 81
25mph 2200 738 55 106

 

topping off the tank may have introduced excessive vapors into the
recovery system.... which gets burned by the engine. so theres your high
HC number.

and idling actually cools the car down.

i wouldnt worry about the test results- you passed.

 

I agree, but I really like the car, and I want it to last...

And if I didn't worry, I might not have taken any precautions before
the test, and been just a few numbers over the max, which would have
hurt.. But then, who's to say?

Randall Fox

 

the one thing you don't tell us is the mileage you have! hc can be
excess fuel [o2 sensor], weak catalyst [excess fuel/oil] or oil [old age].

 

well, ya took the precautions, and it worked. do the same thing next
time- except for topping off the tank

 

The car has about 127,000 miles... It doesn't seem to burn oil. At
least I don't need to feed it oil between changes, if that is any
indication.

I am more worried about the change. I put on 15,000 miles in about
1.5 years, and the smog numbers seem to have gone up
disproportionate... I haven't had any warning lamps or anything..
Gas mileage seems to have been stable during that time as well..

Thanks,

Randall Fox

 

its OBDII so anything seriously out of whack would store a code.

 

agreed, but a sensor may be "within limits" but on its way out. that's
my bet anyway.

 

ok, oil should be ok at that mileage if it's been well maintained.
overall, i agree with mike - you passed this time. just drive & worry
about it when you get a code or if it fails next time.

thing is, despite its good history, you still don't really know the full
story. i had a civic with a problem similar to this. it turned out to
be a very slight coolant leak i'd not bothered to fix. the coolant temp
sensor was not getting fully immersed as the fluid level fell thereby
sending lower temp data that was actual. this fooled the ecu into
injecting the wrong fuel mixture. excess fuel = excess hc in the
exhaust! sometimes it's the little things...

 

Ya, I closely watch for leaks, but I get your point..

As far as the history, I totally agree. A new car is always better
because you aren't stuck with a question mark for the history, but
the price of a used car is really a good deal.. and I never have to
go through the hell of seeing the "first ding" on the car.. Someone
already paid me to put a ding on it...

Randall Fox

 

I llike Jim's theory. It seems to precisely match a condition that I
encountered recently on my 1994 Mazda '626 as well. Like Randall, I barely
scraped through my smog test; and that was on the second go-around. (I
changed out the fuel filter and the plugs and also used the highest octane
gasoline possible before the test). A couple weeks later I smelled coolant
when I parked the car on a slight slope - sure enough I saw a few drips when
I peered under the car. I still haven't fixed the leak, I just top off the
coolant+H2O mix in the coolant reservoir every 4 or 5 weeks. I guess I'll
need to fix it before the next smog check in 22 months though ;-) ;-)

Warning: diatribe against Smog2 follows -

I'm very very PO'd at the state of California for changing the test
conditions under which these measurements are made. Almost seems like they
deliberately did this because they knew a very large number of cars built in
the mid 90s and earlier would most likely have a hard time passing the new
Smog2 limits. Not only does this measure put a lot more dollars into the
(severely depleted) coffers of the state but it also lines the pockets of
umpteen station owners in regions of the state where the new law has been in
effect since 2003. Call me a cynic but I can't help believing that these
scoundrels were probably responsible for lobbying Sacramento to enforce the
new law over a much wider part of the state. (Used to be that only the LA
basin was subject to the stricter test). What I object to is the change in
test conditions from RPM to mph (which largely explains the reason for the
much higher absolute number measurements) ; it's just not very likely that
the average commuter spends more than 50% of their time going at 20mph or
below. That is just silly.

 

ever been on a freeway in so cal during rush hour?

 

I believe that the smog check penalizes people who like to save a
buck. I have an older car because it is just cheaper. I also work on
it for the same reason (and so I know when the mechanic is screwing me
over) . Seems like the state is forcing us to get new cars
constantly..

I just wished they would give free "pre-tests" so that I could work on
the car and get it up to specs.. But I suppose that would be abused..

I know for the next smog check, I will definitely get a pretest and
make sure the thing is compliant before the actual test.

Randall Fox

 

There's something strange about the low speed HC test.

Two years ago, my wife's '87 Toyota FX passed it by 1 ppm. This time, I was
obviously sure it would fail as it is starting to burn a fair amount of oil.
And as luck would have it, I was chosen to be sent to one of those test-only
stations, that are allegedly more rigorous.

You could have picked my jaw off the floor when it passed easily, with low
speed HC way under the limit.

Then my '85 Camry passed low speed HC literally on the limit value. (I sold
it and bought a Honda Element, which is why I'm reading this newsgroup.)

I really think a lot depends on how warm the car is when they do the test. I
had told the folks how I did not expect the FX to pass, and they told me not
to be so concerned, as they ensure the car is completely up to operating temp
prior to starting the test.

Art

 

pre-75 is exempt, as are diesels. you could always buy the title for a
diesel rabbit, and switch the VIN to a non-diesel one

 

was any maintenance done the second time vs the first? even gas
formulations can make a difference.

 

No, In fact the first time the car had recently received its 90K service.
(And I know what you're thinking, but I deal with a shop whose reputation in
this this part of the woods is impeccable.) The second time it hadn't reached
105K, so it had had absolutely zero service in the intervening time span.

Obviously I can't speak for the circumstances of the poster's vehicle, but the
incident with my wife's car didn't surprise the smog check folks whatsoever.
So I thought it worth mentioning.

Art



Art
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