Emissions Question...

[Squeeze]

Gents,

Took my 2000 Saturn SL down to the emissions testing today at it failed, unfortunately. I had high HC and high CO readings. Everthing else passed no problem. Something I didn't realize before I took the car over there is: It does need an oil change, it has been sitting for a couple of months and the gas is probably crap. I did drive the car for about 20-30 minutes before taking it down there. That being said, is there anything else I can do to help bring my numbers down into the "pass" range? Below are the numbers from the print-out that I got from the emissions test. Thanks a million.

HC Maximum: 1.2000
My Reading: 1.7764

CO Maximum: 15.0000
My Reading: 15.1270

Any and all help is greatly appreciated.

[Gman]

Sounds like it's running rich. Is the coolant thermostat stuck open? Happened to me.

[Squeeze]

Sounds like it's running rich. Is the coolant thermostat stuck open? Happened to me.

Not that I can tell. I replaced the spark plugs a few months ago, so we're good there. A friend of mine stated I should decarbonize the motor, clean out the throttle body, replace gas with good quality higher octane gas and dump in some BG 44K then go back after running it for about 30 minutes. Thoughts?

[tmleadr03]

Not that I can tell. I replaced the spark plugs a few months ago, so we're good there. A friend of mine stated I should decarbonize the motor, clean out the throttle body, replace gas with good quality higher octane gas and dump in some BG 44K then go back after running it for about 30 minutes. Thoughts?

Snake oil, and TFOGGER stole my thunder by posting before I could change from a iPad to a computer.

I will add just one question. Is there a check engine light?

[Squeeze]

Snake oil, and TFOGGER stole my thunder by posting before I could change from a iPad to a computer.

I will add just one question. Is there a check engine light?

No. There are no "Service Engine Soon" or "Check Engine Lights" whatsoever. The only fail was the HC & CO. Also, how often should you replace spark plug wires. I replaced them in 2007. The car fires right up but tends to idle real low and does die on occassion at red lights. I was told that is most likely carbon build up on the Idle Air Control Valve.

[tmleadr03]

No. There are no "Service Engine Soon" or "Check Engine Lights" whatsoever. The only fail was the HC & CO. Also, how often should you replace spark plug wires. I replaced them in 2007. The car fires right up but tends to idle real low and does die on occassion at red lights. I was told that is most likely carbon build up on the Idle Air Control Valve.

When you change the plugs. Go get yourself a GOOD set of plug wires (this isn't coil on plug correct?), change the oil, check your air cleaner and you will probably pass.


ETA: Also, while they don't require high end double throw down triple platinum plugs you don't want crap in there. What brand did you use?

[Dave]

I'd check the thermostat like Gman said. At 13 years old, have the plugs been replaced? Don't need any fancy platinums, but with age and probably running rich and not burning all the fuel you may want to pull one and check. High HC (hydrocarbons) is unburnt fuel and high CO is usually either a bad cat or engine running at sub optimal air/fuel ratios.

[Ah Pook]

New oil, filter, gas and air filter. Take it back for round two.

[TFOGGER]

Ok.... High CO indicates a rich condition. Possible culprits: air filter, oil in need of changing, stale fuel.

High HC indicates a misfire, so plugs, wires, anything that could make the engine miss under load.

Replace the air filter, check the plug wires, distributor cap and rotor(if applicable), change the oil.

You may want to dump a couple of gallons of E85 in the tank and fill it with fresh gas, premium is not necessary or particularly beneficial. Make sure there's no exhaust leaks, particularly upstream from the O2 sensor.

[Gman]

GM solid state ignition systems are damn near bullet proof. I'm sticking with my earlier statement. I never had any indication prior to failing my emissions test that anything was wrong. Put in a new high-temp thermostat and passed with fractional values to the max thresholds.

It's pretty amazing how a $5 piece of old-school technology can throw off the new-fangled computers.