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Discussion Starter #1
I have a an AUG 1.8T with a high flow CAT and APR stage 3 turbo and programing. Lately I have been getting CELs every couple of days. The ECU shows codes 16804 which is Cat efficiency low. The MAF is relatively new. Any suggestions on how to proceed? Should I replace my O2 sensor? If so, which one? Thanks, Ray
 

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Here's a pretty good link:
http://www.mr2.com/TEXT/O2_Sensor.html

There's another very informative link I can't find right now that discusses how to log your voltages and analyze the data, but suffice to say you can log the voltages of both sensors and plot them in Excel for visual analysis.

If the whole thing is operating right, you'll see the pre-cat sensor voltage fluctuating rapidly, while the post-cat one will spend periods of a few dozen pre-cat voltage fluctuations in alternating longer low-voltage states / high-voltage states.

Basically, the cat stores up oxygen when the engine is running lean and releases that stored-up oxygen for periods of a few dozen seconds or so when the engine is running rich, so as to burn off excess fuel. And I gather the car adjusts long-term fuel trim based on what the post-cat sensor is sensing.

That's the way I understand it anyway.
 

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RichtsFahren,
Thanks for the links. I have read the information and now understand what is supposted to be going on with the reading from the 2 O2 sensors. I am off now to see how I can read them with the VAG-COM. I will post when I find out something. Thanks again, Ray
 

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God, I get these codes all the time too. I need a freaking VAGCOM. Not to mention a laptop.

Ugh.
 

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Spanky....use the VAG list in the Info forum...you might get lucky. I found two 10 miles from me! :D The one I contacted has been very helpful too! Great community!
 

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There is a guy here in SA that has one, and I know of another in nearby Austin too, but can you imagine a call from me every 2 weeks?

"Hey dude, its Steven again, yeah, um, my cat is still throwing codes, I'm coming over for you to clear it, make sure your wife has that awesome lasagne waiting, thanks." :lol:
 

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Discussion Starter #8
Spanky McGee said:
God, I get these codes all the time too. I need a freaking VAGCOM. Not to mention a laptop.

Ugh.
I got my laptop on ebay for about $200. Its an IBM 600e P2 400 mhz with a 10 gig hard drive and 128meg of ram. I had to load an operating system on it and update all the drivers and bios, but it works like a champ. Then of course is the expense of the VAG.com. All this may be more than you want to spend, but I use the laptop almost as much as my desktop and I havent had any performance problems yet. Of course, it would not be good for memory hungry games.

Anyway, good luck and I hope you get one soon. Ray
 

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Spanky McGee said:
There is a guy here in SA that has one, and I know of another in nearby Austin too, but can you imagine a call from me every 2 weeks?

"Hey dude, its Steven again, yeah, um, my cat is still throwing codes, I'm coming over for you to clear it, make sure your wife has that awesome lasagne waiting, thanks." :lol:
Find out his favorite Brew! Take care of him!!!! :D
 

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Thanks Ray for the info 200 bucks isn't bad at all. When you said you had to load an operating system on it, what did you load, and why wasn't it on there before?

200 bucks is more than I want to spend, but its a nessisary thing to get. Plus, I've got to get one for the standalone sytem coming soon, but come to think of it 200 or so isn't so bad. :weirdo:

:beer:
 

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Discussion Starter #11
I like windows 2000 pro. Very stable. These computers generally do not have a operating system because they are usually being sold by a company that leases them to big companies. When they are turned in at the end of the lease, the hard drive is wiped clean and they are sold on ebay. You have to be careful when buying these, but I have bought several and so far have been very happy.

Regards, Ray
 
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