Just failed California smog check...

[Tangent]

I just failed the smog check and I need some tips on where to start looking. Fortunately I didn't fail horribly so it hopefully won't be major work to get it to pass... I measured 118 PPM HC with 114 allowable and 1008 PPM NO with 785 allowable. I only failed those at the 15mph test, I passed the 25mph test. Here's a scan of the test results:

[aaron_silva]

Go to www.baye30.net and run a search on "smog". There is a ton of info on getting your car to pass California smog that has been covered recently.

Aaron

[B2ThaZiZza]

replace your o2 sensor and make sure you have a clean airfilter and fresh oil/oilfilter and use this also.
i did these things and its a sure bet you will pass.

[Digitalwave]

What mods does your engine have?

[bimmer8604]

you dont have to replace your o2 sensor if it isnt bad, but unless you have an oscilloscope you cant really check it. i would defanitly start by changing some fluids, and maybe running some system cleaner in your gas tank. hth(i dont have to worry about smog, so i dont know exactly all the tricks, but it cant be that hard)

kyle

[Tangent]

The engine is completely stock. I'm running SeaFoam through the gas right now and just ran some through a vacuum line to clean out the combustion chambers. Since NOx is caused by high combustion chambers I'm going to run higher octane for the retest as well as getting an oil change before I go. I'm also going to go for a longer drive than the ~15 minutes I did last time so the cat gets really nice and hot.

[mrsleeve]

Run it on stright methonal or alchool. This is what my little brother did to get his V8 ranger to pass 4cyl emissions in arizona.

He has tried both and each time the headers were slightly hotter than the surface of the sun after the 2 min test :D This is not something I would do with an old tired M20 though.

but it passed with flying colors.

[mspiegle]

i went through this 6 months ago. I replaced wires, cap, rotor, plugs, oil change, O2 sensor, ran CRC and my car STILL failed.

I had to get a new cat installed. Cleaned my car right up and made it a little more responsive.

[Tangent]

I sure hope it doesn't need a new cat already. This car came with complete service records and it got the cap and rotor and fuel pressure regulator replaced ~33,000 miles ago and the cat ~36,000 miles ago. It might be time for new plug wires though, they look pretty rough. They might even be original since there's no record of them being changed...

[aaron_silva]

Was the cat replaced with an OE unit or a universal one? Most universal cats wont last more than a year or two.

Aaron

[Tangent]

Universal... The universal I had on my Camaro was still working great after 3 years.

[aaron_silva]

BMWs are different that Chevys. That is why an OE replacement costs $1200.

Aaron

[Tangent]

Most OE replacements regardless of company are stupid expensive. Years ago I worked for a Honda dealership and a cat for a Civic ran something like $650. BMWs are different than Chevy's, but a quality cat is a quality cat. I used a Random Technologies cat in my Camaro but God only knows what econo-crap cat the previous owner might have installed in my E30...

[bmwman91]

Yeah, your #'s look exactly like mine did. Replaced thermostat, fluids, ran steam through the engine to remove the "mystery carbon deposits", system cleaner, and still failed.

Got a new cat, passed like it was new. Just get a new universal 3-WAY & you will be fine. Don't bother with running ethanol or any of that stuff, just do it right & replace the cat.