Smog Check Question and High HC

[kzkevin]

Hi Eric,

Can you do a video about like Emission Testing. Like High HC, High CO, or High NO?

I tune up my 98 camry v6 before I took it to smog. Like genuine toyota parts. Spark plugs, Spark plugs wire, air filter, oil change, etc. It has high HC still but it passed smog. I dont think it will pass next year 2013. How can I bring down the HC numbers. I know it is unburnt fuel but Can Coil pack or the Ignition Coil go bad over time. I have no CEL. It has 129k on it.

It wont let me attach the pdf.

15mph Hc max ave meas 52 9 51 CO 0.49 0.02 0.04 NO 424 57 173
25 MPHH MAX AVE MEAS 36 7 17 CO 0.46 0.03 0.06 NO 711 50 197

15 mph % C02 is 15.1 %02 0
25 mph % c02 15.1 %o2 0

But like my sienna and 91 accord has the Co at 14.6 % and measured at 0.3 o2%

If you like I can email u the report directly.

I think a lot of people have this question.

Attached is the smog check report. I also attached two other car they passed but how come the accord and sienna have o2% reading. Is that bad? What causes it?

Thank you

Topic

[college man]

yes a ignition coil can go bad.it may still work but
may be putting out a weak spark. do you have a cel on?
does the car run rough?

[EricTheCarGuy]

I sort of have done a video on emissions testing with my friend ScannerDanner.

[kzkevin]

No CEl. Car runs normal. Can I test the ignition coils. It is not those distributor ones its distributorless.
Thanks

[college man]

try doing a power balance test.

[EricTheCarGuy]

If the car runs normal I wouldn’t worry about the ignition coils, if one of them was having an issue it would likely cause a misfire so lets put that on the shelf for now.

The car and engine are old and worn out. As a result the HC emissions will be higher and there is little you can do about it other than replace or rebuild the engine. You might check the O2 sensor readings with a scan tool. With those older cars it allowed for a ‘slow’ sensor to stay in play whereas later models did not have such loose tolerances in their programming. If you watch the O2 sensor readings and you don’t see much fluctuation then perhaps it’s getting ‘slow’ and replacing it can improve HC emissions. If it’s got a rapid fluctuation then that would indicate it’s normal and doing it’s job and if that’s the case then as I stated your engine is probably worn and causing the higher than normal HC readings.

[Author]

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