Failed CA Smog Test Twice
 

Hi - i have a second car (a 00 Toyota Celica GT-S) that I use as a daily driver. The car recently failed smog twice, and I'm hoping to get some feedback. The car has 170K miles, has a smog certified intake and muffler. No other mods. I recently put on a new O2 sensor, PCV valve and Cat converter (OEM style, not a high-flow).

Anyways the first time in Sept, I failed due to high HC and high NOx - the HC was 181PPM vs. the 64PPM maximum allowed and the NOx was 1734PPM vs. the 477PPM max. Basically, i failed the tailpipe test miserably.

After failing the test, I put in new spark plugs (the other ones were iridium with 95K on it, changed the oil, and cleaned out the fuel system. I even overinflated the tires prior to the test. This is because they put the cars' drive wheels on a dyno type of device to simulate "real driving conditions" up to 2500 RPM. I've heard that by overinflating the tires, you reduce the load a bit which helps reduce the tailpipe results. I even got the car hot by driving high RPM on the freeway to make sure the cat would function well.

Long story short, I failed again - this time only on the HC at 75 PPM vs 64 PPM max - I was much closer to passing the second time.

Since I have a new converter, o2 sensor and everything is functioning properly, I don't know what else to do. Please let me know if you guys have any thoughts.

thanks

Other than the cat not being quite up to spec, only other thing I can think of is the intake -- OEM intake box or pod-type filter? If intake is OEM, try cleaning the MAF sensor -- could be the car is runing a bit rich.

Are you throwing any blue smoke? I had a Toyota that was near failing until I had the head gasket redone. Then it went back to near original on the emissions.

I had a 93 MR2 Turbo that had trouble passing emissions test. Like you, I had just done a tune up on it myself. I took the car to Toyota and they said nothing wrong with it and passed it on their own emission test. The guy there said it has to go in hot off the road to pass. You cannot stay long in a line idling or you will not pass, this was my mistake. If mine went in hot on a drive up, it passed easily, but if I drove up and waited in line for long, it would fail. Find a shop with no line, if you have been driving for awhile take her straight in, otherwise take a couple of laps up and down the street first.

I'm so glad South Carolina doesn't have emissions tests. I feel for your guys having to jump through hoops.

As they said, get it really really hot. Turn your AC on to help raise the temp. Did you do engine flush? You may also want to run a bottle of Techron. I heard that a botltle of "pass smog" may help.

If you have a broken head gasket, well.....

You do realize that the state would give you like $500 to get it repaired? I have a beat up Miata that I applied for the assistance. Or, consider selling the carnto the state.

Oh, on google on "failed smog high hc". The below is one sample. Good luck!

What causes high HC. What causes high Hydrocarbon - SmogTips.com. Failed HC Emissions. Why did my car fail the emission test for high HC emissions. What is HC. My vehicle failed the emission test for high Hydrocarbons. Why my car produced high HC. Hi

thanks for the tips, I ended up buying a bottle of CRC Guaranteed to Pass ran it through a tank, inflated the tires up to 45PSI and it passed.

It also helped that the smog sniffer partially fell out of the exhaust when he revved the engine.

Good job! Smog in Cal sucks, but heck, our air IMHO is getting cleaner!