"Howard Lester" wrote in news:NbKdnaAWIZhU5dDUnZ2dnUVZ snipped-for-privacy@posted.dakotacomip:
"Tegger" wrote
>
> >> Here's all the history Az DOT has.
>>>
>>> HC Idle HC Load CO Idle CO Load.
>>> (220 ppm) (220 ppm) (1.2%) (1.2%)
>>>
>>> 2004 173 82 .34 .52
>>> 2005 181 74 .21 .46
>>> 2006 207 100 .56 .64
>>> 2007 219 105 .4 .46
>>> 2008 190 157 .6 .57
>
>
>> Numbers are incomplete. No NOx. No CO2.
>>
>> Does AZ not test for NOx?
>
> It's been many years since I've had to have a full test on my car, as
> I kept buying new ones, and new ones are exempt from inspection. But
> seeing the above HC and CO testing, that's about what I remember being
> tested. So I suspect they don't test for NOx, though in reference to
> the catalytic converter inspection (on the right side of this sheet)
> there is a notation about NOx:
>
>
formatting link
> Note that this sheet is titled "Emissins Control Visual
> Inspection...." Our state legislature never had much interest in > education, you see.
>
>
All right, assuming NOx and CO2 are unavailable, I can think of a few things off the top of my head. This is in no particular order, so do the easy, cheap stuff first.
Remember that HC is simply raw gas that's getting out of the combustion chamber without having been burnt up first. CO is incomplete combustion, from too much fuel and not enough oxygen (the resulting combusted molecule has only one oxygen atom instead of two).
1) Check the cat inlet and outlet temperatures. Take the car out for a drive sufficient to warm the engine up to full operating temperature. A bit of high-speed driving is a good idea. When measured with an infrared thermometer, the cat should have an outlet about 30-100 F higher than the inlet. If in and out are the same, or the outlet is cooler, the cat is either insufficiently warmed up, or it's no longer working anymore. 2) Do you have EGR? Partially-plugged EGR can cause across-the-board high emissions, which is why I asked about NOx. 3) Retarded ignition timing. You'd be dumping raw gas directly into the exhaust manifold, expecting the cat to do the clean up, something it's not designed to do. 4) Dirty injectors with poor spray pattern. Run a Motorvac service (~$100), which is not a bad idea even if there's no actual issue to solve. 5) Thermostat too old and stuck open. Will cause rich running and high emissions. 6) What do the spark plugs look like? What kind and color of deposits on them? Do they show signs of proper spark? Have you checked each plug wire to make sure you get a purply-blue spark at each one? (Use a spare spark plug to check in a dark garage or at night.) 7) How old is the oxygen sensor? Is it OEM or aftermarket? An old sensor will result in poor control of fuel mixture.