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dualaudi
03-12-2008, 11:55 AM
Okay, So I think my secondary (after cat) o2 has a cut wire or something. Will this effect drive ability if it's disconnected or broken?


I have been experimenting with my aFPR on this tweaked ATP tune that calls for 550's. 580's were lent to me and working really well for 2 days, then gave those back and put the 630's on, way too rich, but still worked. tried 440's and way to lean.

Put the 580's back on and I'm at 70psi (anything lower and i can't even drive in boost) and i should be rich as f#$@, but i still get miss firing a little while in any kind of boost... plugs are a bit white

yes 317ssayzarc, I know ATP sucks balls... i'm going to prob get ctapp tune for the 4"maf. although the uni tune would be easier w/ 440's and my 3"maf

317ssayzarc
03-12-2008, 11:59 AM
ill answer your question first... just unplug the rear 02, you will just get a code for is but all that 02 sensor does is its a tattletale for cat condition, aka emissions... the plug is located right under the coolant bottle...


yes 317ssayzarc, I know ATP sucks balls... i'm going to prob get ctapp tune for the 4"maf. although the uni tune would be easier w/ 440's and my 3"maf

now on to this lol, i have nothing against atp hardware and such but the MIKA tuning is shitty... tapp or uni will be just fine [up]

dualaudi
03-12-2008, 12:47 PM
Okay, yeah, I just wasn't sure if disconnecting it would effect fuel trims or anything else injector related. Now the long road to getting my fueling fixed till I can get a new tune.

(all I have to do when swapping injectors is disconnect the ECU for a few mins right? Or should I be using a VAG to reset the fuel trims?)

dualaudi
03-20-2008, 07:57 PM
So you're sure my secondary o2 won't efect how my car runs? The wires may have been frayed and crossed/shorted, so i have it unplugged...

Can I plug my wideband into my secondary oxygen sensor? Will I ruin anything or will it work the same way my seconday works?

317ssayzarc
03-20-2008, 08:49 PM
wont ruin anything, you may get a cel...

my tapp software doesnt require me to run that 02 sensor to keep the cel off, i just need it plugged in to keep the heater circuit happy, i have a wideband in that bung instead though

bradisonn
08-05-2008, 06:54 PM
how do you unplug the red oxygen sensor connector? sry if this is really noob but i dont wanna break anything off...

GetBoosted84
08-05-2008, 07:20 PM
Can I plug my wideband into my secondary oxygen sensor? Will I ruin anything or will it work the same way my seconday works?

If you are running a cat then plugging a wideband in behind the cat is not a good idea. Your readings will be off. If you are straight piped then no big deal.

bradisonn
08-06-2008, 12:15 AM
i was replacing my rear sensor today and for the hell of it i ran a vag-com while the sensor was unplugged...it gave me the same exact reading. does it take some time to reset or recognize the change?

note: i only had the red plug undone, the actual sensor was still in the catalyst.

Thanks in advance!

MattzWarsteiner
08-06-2008, 12:49 AM
O2 sensors don't say much for the first minute or so after you start up. The ECU should have reported an open heater circuit tho. This is monitored right away.

bradisonn
08-06-2008, 08:13 AM
yeah, i got that code also. so i should be fine a few minutes after the install? I just want to pass my emissions test (fcking money grab)....

dualaudi
08-06-2008, 09:35 AM
Bradisonn, are you quattro? as long as you have that O2 code taken care of you should pass with flying colors on a stock or chipped/k03 with no problems.
(provided no other codes pop up)

Just remember after you clear your codes, you have to make sure your ecu is in readiness mode for the test... some say 50 miles driving others - 300...

I have an article that says you have to do a lot of different driving styles for this to happen - like do some 0-25mph w/in so many seconds, go from 45 - 0mph a few times... stuff like that.

bradisonn
08-06-2008, 10:56 AM
no, not quattro. i had no other codes pop up before, so i think after this i should be good. what exactly is readiness mode? Is that something that I program using Vag-Com or is that just driving for a certain amount of time before i take it in? Thanks for you help btw!

MattzWarsteiner
08-06-2008, 02:35 PM
Readiness is when the ECU is getting good data from the various sensors. The engine has to be running for at least a few minutes with all of the emissions controls working and sensors ready.

Not sure how the mileage trick with bad sensors/controls works to fool the smog test equipment. Someone else here knows more I am sure. .. ....

bradisonn
08-06-2008, 04:26 PM
well once i get the new sensor installed i wont have to do any tricks haha.