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OC Smog HELP! :(

28 May 2003
The OC, CA

Took my baby in for smog this last weekend and it failed like a hung over college student taking finals.. :frown:

Here are the numbers..



MAX: 86 697 724
AVE: 21 150 136
MEAS: 135 1555 793

I did a search and saw the suggestions about using 87 octane, checking the EGR, heating up the cats.. etc. Any yeas or nays to any of the advice?
Suggestions on where I can take her to have her checked out?

If anyone here knows where I can have the car tested again before running the real test please sound off.

Any and all advice is appreciated..

Oh, I forgot to mention, DC Headers and Comptech (old school SuperTrapp) Exhaust
Take it to Shane @ Autowave in Huntington Beach.

Also, how many miles do you have? Consider changing the plugs, oxygen sensor, and the air filter.

Do you have to take it to the 'smog center only' station? If it is, it would tough to go around that.

Does the exhaust fume smell funny? It may be your cats?
hey guys,

thanks for the replies..

96K miles.. had the major 90K service done less than a year ago....

I have to take it to a "test only" center and the I haven't noticed the exhaust smelling funny or any smoke coming out when I first start the car..

please keep the suggestions coming..


I take it no check engine lights. Have you pulled any codes? Look at the breakdown on your 90k mile service to see exactly what was done. I would check w/ Autowave and don't shoot in the dark by changing things without diagnostics. Also, if you are not the first owner was it a CA car before? Did the previous owner (if applicable) modify anything on the car aside what was mentioned? Did it have any history of failing? Good luck.

Super high NOX but with HC at passing levels is usually a result of a bad cat (usually) or oxygen leaking into the exhaust system (rarely). Usually the NOX is many times the max levels.

A very high HC (at or above max) can also shoot this value higher as a result of improper air/fuel ratio at slow speeds, causing the engine to run rich. You can tell as the engine gains momentum the fuel trims out and the values come down, so I would suspect your O2 sensors, mass air flow sensor, and possible fuel contamination.

Good luck!
Try this out.

Always worked for me.

-best octane gas you can get.
-1 can of octane booster ( high quality )
-make sure your car is running tip top with new plugs, air filter, new oil a given.
-retard timing 5 degress ( they never check )
-drive your car for at least 10 minutes at highway speeds to get your cats heated up properly.
-ask the smog guy to keep your car at 4000 rpm+ for 2 minutes just before the test.

You should be good to go.

I have gotten really old cars with drop dead smog results to pass with out new cats... lol. last time i passed by 1 point :biggrin:

I gota get my NSX smogged too. The previous owner hacked off the factory piping and cats so im in process to get tho bits. I'll see howevery thing comes along with my car.

GL on yours.