Anyone got an ideas of passing emissions i failed it twice..... have no cats but my o2 sensors read ok and they have been ok since last year when i did pass....so in other words got any tricks to "eliminate my o2 sensors" so i can pass? im in missouri by the way and have an 00 s4

 

lol, dude, not having cats is a pretty sure way to fail emissions. Surprised they even let you attempt it...usually they take a mirror and look underneath the car to make sure your CATs and O2s are in order.

That sleeve they put over the exhaust -- it's measuring emissions. You're not getting past that part unless you sleep with the crusty old chick running the emissions station or you install a pair of CATs.

Yes, they also plug into the OBD-2 port...that part you can fool by soldering a diode into the (+) voltage line from each of the downstream O2s. Thus, you can get rid of the CEL that comes up as a result of ripping out your pre-cats. (Disclaimer: doing this is illegal, I don't endorse it. If you get into any legal trouble, I am in no way responsible

Did you scan with your VAG? Are you currently throwing any codes?

 

i think that you can bypass the actual im 240, or what ever gas analysis they do there if all of your readiness codes are set, and you have no codes. i was once a certified missouri technician, certified to do repairs on emission failure cars. (years ago...lol) if you can pass the OBD11 tests, then they will not do a gas analysis, unless it has changed in the last 5 years. or get an address out in warrenton or something, that way you only have to pass safety inspection and not gas... i think its only st.charles county and st.louis county, correct?? that does gas analysis??

 

Good to know. I was planning on welding in a pair of CATs for my upcoming smog test. Not sure how they do it in Colorado, but, if I could skate by with only having to *ahem* work on my O2s -- that would be much less expensive.

Any idea how it's done in Denver? How can I find out?

 

http://www.aircarecolorado.com/default2.htm

 

I'm in Missouri and the shop I got to knows I don't have cats but when I was on the machine with the obd2 it said It couldn't read o2 sensors. Where is the(+) voltage on the o2 sensor in the wire in the pin etc and where do I get diode from? Thanks for the heads ip oh and Missouri doesn't do gas analysis do you know of a county other than stl that doesn't have the stupid electronic emissions test?

 

they only counties that did the sniffer tests or gas analysis tests where the ones with st. louis, st.charles/st.petersburg, and MAYBE kansas city. thats why i suggested warrenton, or maybe lake st. louis (not sure which county its in)

 

go here:

http://www.audiworld.com/tech/eng.html

edit:

Oops, forgot to add -- go to the oxygen sensor modification article