Results 1 to 17 of 17

Thread: Anyone able to code out 02 sensors and MAF CEL?

  1. #1
    Registered User
    Join Date
    Dec 2005
    Location
    Wisconsin
    Posts
    115

    Anyone able to code out 02 sensors and MAF CEL?

    I have my car tuned with gutted pre cats. I need to get my precat o2 sensors and MAF overlimit codes removed so I can go through emissions. Been driving with the CEL on and no registration for a long time now, need fixed.

    Thanks

  2. #2
    Registered User ttboost's Avatar
    Join Date
    May 2009
    Location
    CT
    Posts
    2,457
    You cannot code out front O2's and MAF's. Those are the only thing keeping the car running right. Rear O2's can be coded out. Have you scanned for codes?
    2013 Audi S8

  3. #3
    Registered User
    Join Date
    Dec 2005
    Location
    Wisconsin
    Posts
    115
    Yes, I have the codes are P0103, P0174, P1455. P0420, P0430.

    None of these came up until the moment I had the reflash.

  4. #4
    Registered User hahnmgh63's Avatar
    Join Date
    Feb 2007
    Location
    Roy, WA
    Posts
    3,305
    P0174-too lean Bank2, EGT1, these you should not have. The P0103 can be avoided before your test by clearing the code and driving the car easily for the minimum mileage needed before the test, something like 20 or 30 miles after clearing codes before they will usually let you test. The P0420 & P0430 can be fixed by coding out your rear O2's. You shouldn't be getting the 'too lean bank 2' or the EGT1 codes. Who did your tune? How many miles on the car?
    2003 White RS6 2013 Midnight Blue S5
    2013 Daytona RS5 2x944 Turbo's 1974 911 w/'91 3.6ltr motor
    Roy, WA

  5. #5
    Registered User
    Join Date
    Dec 2005
    Location
    Wisconsin
    Posts
    115
    I have 130k on the car, not one code up until the day it was tuned, I don't want to say who tuned it, he is trying to work on a fix for the problem, but seems to be having trouble. So I am looking for anyone who can tune the o2's out...

    I have winols, but have no clue how to use it, and cannot read german. Lol

  6. #6
    Registered User 10SecS4's Avatar
    Join Date
    Aug 2007
    Location
    East Coast, USA
    Posts
    357
    Are you sure it's P0174 and not P1074? P1074 is the same as your P0103 code except for the other bank.

    Quote Originally Posted by nitrorocket View Post
    Yes, I have the codes are P0103, P0174, P1455. P0420, P0430.

    None of these came up until the moment I had the reflash.
    I tune RS6s. Smooth, powerful, safe & affordable. Proven results. PM me for more info
    Mugello Blue RS6 \ 206K Miles \ Tune Only \ 11.93 @ 116.9 \ http://y2u.be/TqE3-JzYCig \ Daytona Grey RS6 \ Tune, Decatted & Exhaust \ 11.59 @ 118.6 \ http://y2u.be/hqawHXwWcOU

  7. #7
    Registered User lswing's Avatar
    Join Date
    May 2011
    Location
    Eugene, OR, again...
    Posts
    4,760
    I'll get front O2 and EGT intermittent when running lean and hot....you can cook those egt's costing you $, and the O2's might not like it much. Since you're playing with fire, and seem to have VAGCOM, go log Timing, EGT's, and Lambda values, will let you know if the tune is wreaking havoc. Also could just be old plugs or fuel filter inhibiting a good strong tune, or....
    Ace/Edge TC - Tozo Trans - MTM TCU - REVO/ME7 tune - Wagner IC's w/ Venair Hoses - Aux Radiator delete - Hotchkis Sways - Hawk HPS Pads - Koni Sport Struts - Scroll KO4 Turbos - Devil's Own WM - 421whp/452wtq on Mustang Dyno - http://www.audirssix.com

  8. #8
    Registered User
    Join Date
    Dec 2005
    Location
    Wisconsin
    Posts
    115
    Marc, it is P1074, apparently I need to work on my typing skills. haha.

  9. #9
    Registered User
    Join Date
    Dec 2005
    Location
    Wisconsin
    Posts
    115
    It's not because the car is running hot, I can drive around normal at part throttle and though codes will come back driving without boost. The MAF code only comes on when I'm boosting hard.

    Anybody able to code out the O2 sensors?

    Either that, or I need to put my computer back to stock so I can get through omissions. Not really thrilled about driving around in an unregistered car anymore That has a check engine light on all the time.

  10. #10
    Registered User lswing's Avatar
    Join Date
    May 2011
    Location
    Eugene, OR, again...
    Posts
    4,760
    Quote Originally Posted by nitrorocket View Post
    It's not because the car is running hot, I can drive around normal at part throttle and though codes will come back driving without boost. The MAF code only comes on when I'm boosting hard.

    Anybody able to code out the O2 sensors?
    You should log data, and find then fix the problem, it would help your car greatly. Why would you code out a sensor that is trying to help you? Plus you'll get better performance with the car buttoned up...

    If it's just MAF maybe it's a small leak, sometimes a good shop can fix you up quick!
    Ace/Edge TC - Tozo Trans - MTM TCU - REVO/ME7 tune - Wagner IC's w/ Venair Hoses - Aux Radiator delete - Hotchkis Sways - Hawk HPS Pads - Koni Sport Struts - Scroll KO4 Turbos - Devil's Own WM - 421whp/452wtq on Mustang Dyno - http://www.audirssix.com

  11. #11
    Registered User
    Join Date
    Dec 2005
    Location
    Wisconsin
    Posts
    115
    It's not because the car is running hot, I can drive around normal at part throttle and though codes will come back driving without boost. The MAF code only comes on when I'm boosting hard.

    Anybody able to code out the O2 sensors?

    Either that, or I need to put my computer back to stock so I can get through omissions. Not really thrilled about driving around in an unregistered car anymore That has a check engine light on all the time.

  12. #12
    Registered User
    Join Date
    Dec 2005
    Location
    Wisconsin
    Posts
    115
    Its not a problem with the car, none of these codes were active until the day I installed the flased ECU.

  13. #13
    Registered User lswing's Avatar
    Join Date
    May 2011
    Location
    Eugene, OR, again...
    Posts
    4,760
    Quote Originally Posted by nitrorocket View Post
    Its not a problem with the car, none of these codes were active until the day I installed the flased ECU.
    The tune will ask more for the car, therefore exposing problems such as an air leak. What tune is it? If you're that unsure of the tuner I would pull it from the car anyhow, but it's a problem with the car is my guess.

    If you're not logging data to see just what is going on you're playing with fire...
    Ace/Edge TC - Tozo Trans - MTM TCU - REVO/ME7 tune - Wagner IC's w/ Venair Hoses - Aux Radiator delete - Hotchkis Sways - Hawk HPS Pads - Koni Sport Struts - Scroll KO4 Turbos - Devil's Own WM - 421whp/452wtq on Mustang Dyno - http://www.audirssix.com

  14. #14
    Registered User 10SecS4's Avatar
    Join Date
    Aug 2007
    Location
    East Coast, USA
    Posts
    357
    He's not playing with fire because his code was P1074 not P0174. His codes are for the two rear O2s (since he gutted the pre-cats) and signal too high for the MAFs which is common for a strong tune since it's running the maximum airflow for the stock sensors.

    Quote Originally Posted by lswing View Post
    The tune will ask more for the car, therefore exposing problems such as an air leak. What tune is it? If you're that unsure of the tuner I would pull it from the car anyhow, but it's a problem with the car is my guess.

    If you're not logging data to see just what is going on you're playing with fire...
    I tune RS6s. Smooth, powerful, safe & affordable. Proven results. PM me for more info
    Mugello Blue RS6 \ 206K Miles \ Tune Only \ 11.93 @ 116.9 \ http://y2u.be/TqE3-JzYCig \ Daytona Grey RS6 \ Tune, Decatted & Exhaust \ 11.59 @ 118.6 \ http://y2u.be/hqawHXwWcOU

  15. #15
    Registered User lswing's Avatar
    Join Date
    May 2011
    Location
    Eugene, OR, again...
    Posts
    4,760
    Quote Originally Posted by 10SecS4 View Post
    He's not playing with fire because his code was P1074 not P0174. His codes are for the two rear O2s (since he gutted the pre-cats) and signal too high for the MAFs which is common for a strong tune since it's running the maximum airflow for the stock sensors.
    Got it, seems like an easy fix then. So why the problems? Just code out the rear O2's which is standard, and don't flog the car for a few miles after clearing codes as mentioned.

    Actually first time in years I've heard about the MAF exceeding because of a strong tune. Lots of people seem to have their car tuned to the edge without this issue. Again, would be nice to see a log...

    Edit; Boost leak is a common reason for the MAF code...
    Ace/Edge TC - Tozo Trans - MTM TCU - REVO/ME7 tune - Wagner IC's w/ Venair Hoses - Aux Radiator delete - Hotchkis Sways - Hawk HPS Pads - Koni Sport Struts - Scroll KO4 Turbos - Devil's Own WM - 421whp/452wtq on Mustang Dyno - http://www.audirssix.com

  16. #16
    Registered User G2's Avatar
    Join Date
    Apr 2012
    Location
    Eugene, OR
    Posts
    695
    Won't that be for naught, when actual tailpipe emissions are measured during the test?

    The PPM counts will be drastically higher w/o a functioning cat. system. Can't see how turning off the MIL (not CEL folks, that's domestic auto talk there!) light is going to help much. At least the AWD system makes it exempt for a loaded dyno test.

    Either way seems a shame to pollute 10 to 100X more just for a few more HP.........
    Cheers, G2/Gary
    C5-RS6/KWV3/Revo/H20 Inj./Custom BBK/Custom cooling/CNC arms \ VW Touareg V10 \ B7A4 2.0T Avant \ Mk1 Callaway Scirocco \ audirs6parts@gmail.com / www.oilpro.myamsoil.com

  17. #17
    Registered User hahnmgh63's Avatar
    Join Date
    Feb 2007
    Location
    Roy, WA
    Posts
    3,305
    Believe it or not, most states, including across the border here in Washington just plug into the OBDII port and don't even sniff the exhaust on an OBDII car. Some are stricter and do the sniff test and a couple even do the above and below visual inspection looking for modifications.
    2003 White RS6 2013 Midnight Blue S5
    2013 Daytona RS5 2x944 Turbo's 1974 911 w/'91 3.6ltr motor
    Roy, WA

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •