The high NOx makes me think the EGR is not working.
1997 Chevy Cavalier failed emissions testing
- Thread starter 97prizm
- Start date
heats up the CAT and makes it function more efficiently lowering both NOx and HC
loosens carbon in rings, frees rings, increasing sealing, and lowering HC emissions
may free carbon on spark plugs, lowering spark plug temp (lowering NOX), or increasing burn efficiency (lowing HC)
may help clear deposits on injectors lowering HC
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I'm surprised the CEL isn't on if you failed emissions 
I thought only California still required sniffers on post-96 cars
Sell the car to someone in an non-emissions county
I thought only California still required sniffers on post-96 cars
Sell the car to someone in an non-emissions county
No Colorado got rid of the 25 year "classic vehicle" plates a few years ago. Not sure who or why they did this.
If you already had a set did you have to buy new ones?
Probably because people were registering 25 year old Civics and F150s as classics to avoid inspection and using them as beaters,
No i considered going this route as I hardly ever drive it. The struts are bad, it needs a head gasket and i bought a radiator for it as the radiator has a small leak.
I was referring it to being an OBD2 car. Mandated in 1996. Why are they using a tailpipe sniffer?
Colorado is in bed with the epa and testing procedures. Apparently there is a 7ish year exemption on new vehicle emissions then the next 10 years I think are obd2 plug in after that they are all tailpipe tested. I wish Colorado would just do away with emissions testing for good.
Probably because of people gaming the system. Resetting the check engine light, then driving it until the required number of monitors have been set but before the check engine comes back on and getting it inspected.
I could do that with any OBD2 vehicle regardless of year.
Its much easier to cheat a sniffer than OBD2.
Is there a prescribed law that says older than whatever date it must be done with a sniffer? - edit - @97prizm answered this above.
Years of Colorado Emission testing behind me thankfully. I was always told that fresh oil was a trap for HC, so I always changed it before I did a test. I also added a few gallons of E85 a couple of days before every test too.
Thankfully I'm out of the e-test area now.
Thankfully I'm out of the e-test area now.
I'd say just the opposite. With OBD2 you can monitor the emissions system and see when its ready to pass. On a sniff test, you have no idea unless it's so obvious when it won't pass.
Get the engine fully up to temperature and clean the spark plugs, as max power is max heat, pressure and airflow through the intake, heads and exhaust.
I'm going to replace the spark plugs change the oil and maybe throw in a bottle of "guaranteed to pass" and see if that does the trick.
Doesn't everybody do this? It's perfectly legal.
Today I learned that there is a 1997 Cavalier still on the road.
I've got a 2000 with the 2.2 sitting here right now. It's only got about 157k, though.
If you're after an econobox, they're not terrible. A Corolla or Civic is probably a better choice, but with a higher price tag for the cachet -- er, well, as much cachet as a Corolla can garner.
The 2.2 even gets some praise here:
2000 Cavalier 2.2 engine porn
Saw the other thread like this and was replacing a leaky valve cover gasket today so figured why not snap a pic. Car has 135,000 miles on it, I purchased it back in 2007 with about 50k on it. Hasn't moved for the last 3 years. Before that, it got Rotella 15w-40 every 5,000 miles.
bobistheoilguy.com
Yes legal but was responding to the comment that sniff tests are easier to circumvent than the obd2 test.
