Smog Test Result Comparison

[cfg83]

Hello -

I got my California smog test in August 2007 :



As stated in another thread, my car passed with great numbers for HC and CO pollution (below the average !), but the NOx was higher than normal. I did have the HAI (Hot Air Intake) online, so maybe this is an effect of the (mild) lean-burn. I think the IAT was running over 125 degrees F when I got the test.

My wife just got her 2003 Civic Coupe tested :



Other than the numbers for the NOx, which are still well within legal limits, my old SW2 is holding up well. My wife's Honda is bone stock, but is also pushing the NOx above average. For each test you can see that the maximum allowed emissions are a wee bit lower across the board. I expected a bigger difference between 1999 and 2003, but I am actually happier that my 4 year older car is being held to close to the same standard. Maybe the maximum emissions is a function of the displacement of the cars. I have a 1.9 liter engine, and she has a 1.7 liter engine.

CarloSW2

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[Cd]

Thanks for posting.

( I can't see your images though . )

I'll have to post my results too.
I would love to see more peoples results, and find out what mods help / harm our emissions score.

[cfg83]

Cd -

Originally Posted by Cd

Thanks for posting.

( I can't see your images though . )

I'll have to post my results too.
I would love to see more peoples results, and find out what mods help / harm our emissions score.

Thanks for telling me. I had a broken Internet connection last night, so I think I lost the image download during the posting.

If I *really* had my act together, I would do some smog testing with gizmos on and off to see what happens, just like you say.

CarloSW2

[Christ]

They're both OBD-2... They should be held to nearly the same standard of emissions requirements... obviously, engine size makes a difference, but probably not to a huge extent when you're only talking about .2 liters of displacement.

[Duffman]

I'm not suprised that your WAI raised NOx. NOx is created by high combustion temps and you took some of the cooling that is supplied to the cylinder away.

[cfg83]

Hello -

Update on my emissions. I passed, but my NOx is really high, so I am . I kept the WAI for this new test because I wanted to make the comparison test otherwise equal between 2007 and 2009.





I figured out that the 25 MPH test was done in different gears. The 2007 test was done in 3rd gear, but the 2009 test was done in 2nd gear. I made a spreadsheet that "cross-derived" the NOx emissions for a better comparison :



Essentially, my NOx jumped 400% from two years and 39K miles ago. Based on the above trend, I can tell that my (25 MPH) NOx will be non-compliant within the next 6 months.

My HC PPM is also way up, but I think that if I solve my NOx, I will solve my HC.

My one year goal will be N-fold :

1 - Get the car tuned up. It's mostly just been regular maintenance and as-needed repairs (radiator and water pump). I do have a P0410 error code (secondary air injection pump), but I think that plays only a small (engine warm-up) part of emissions.

2 - Do an oil analysis (pending).

3 - Retest with and without the WAI. I talked to the smog dude and I can pay him to do a non-DMV smog test.

4 - Maybe do an Auto-Rx style treatment. I have some stuff called XcelPlus "Engine Protection" and "Upper Cylinder Treatment". It's been sitting in my garage for a few years. If I can verify that it's chemically stable, I will probably try it out.

5 - Maybe get a new set of spark plug wires. I am positive that I have my original wires. I want either OEM or Magnecor.

I'm hoping I'm not approaching an engine rebuild. I don't think I can't justify keeping my SW2 if I have to do a rebuild, but the emotional part of me wants to "find a way".

CarloSW2

[roflwaffle]

Don't worry about an engine rebuild. We have ways (legal ones!) of making you pass smog.

I don't think your HC levels are really that high. NOx is through the roof, so an interblag search says to check EGR, ignition timing, and O2 operation, which you should be able to do on your own w/ a service manual and a DMM. If you have a SG, maybe check ignition timing w/ and w/o the WAI (on the safe side, reset the ECU and you take the WAI off, although I'm not sure if that needs to be done w/ OBD-II cars) to see if there's any change.

[some_other_dave]

...And stay away from that "upper cylinder treatment" snake oil... A good tune-up should bring the levels closer to where they should be. Pulling the WAI will probably drop the NOx and raise the HC/CO a little.

-soD

[cfg83]

some_other_dave -

Originally Posted by some_other_dave

...And stay away from that "upper cylinder treatment" snake oil... A good tune-up should bring the levels closer to where they should be. Pulling the WAI will probably drop the NOx and raise the HC/CO a little.

-soD

Ok. I'm posting the same results onto saturnfans because theyz knowz mee Zaturn :

California Smog Test Results.. (Look at post #7)

The first thing I am going to do is get new ignition wires. I am 80% sure I have the originals.

CarloSW2

[Cd]

I'll have to get some images up with my own results.

Can we get someone with a hybrid, or a PZEV to post their results ? I'd really like to see how we all compare.