Audizine - An Automotive Enthusiast Community

Results 1 to 7 of 7
  1. #1
    Senior Member Two Rings Protection's Avatar
    Join Date
    Feb 24 2011
    AZ Member #
    71438
    Location
    Long Island NY

    Catalytic converter recommendations

    Guest-only advertisement. Register or Log In now!
    So my aftermarket cat died (Bosal) after only 5 years. I killed the original 11 year old cat 5 years ago by driving 5 hours home with an ignition coil not working (I know I should have unplugged the injector I suspect the raw fuel coated the cat and perhaps ignited inside)!but that was the original not the crappy Bosal

    Anyway, on the 1.8t this job is a bit of a pain, so I prefer to not have to do it again in 3 years. Iím certain it is the cat because i have scoped both 02 sensors, and the oscillations on the rear 02 are largely following those of the front (I am getting a code for cat below efficiency). I tried the old O2 spacer on the rear sensor, but now the readiness code wonít set for the cat, and I am getting a code for rear 02 sensor ďresponse too slow.Ē

    Does anyone have an aftermarket cat they are happy with? I have heard some positive reviews of the 034 high flow. However it is marketed for ďoff roadĒ and not approved for street use. Iím in NY where they donít use a sniffer. As long as readiness codes are all set without a MIL light you are good to go. Iím more interested in longevity than performance at this point.

    Thanks


    Sent from my iPhone using Tapatalk

  2. #2
    Veteran Member Three Rings
    Join Date
    Jul 03 2010
    AZ Member #
    61005
    My Garage
    1988 Merkur XR4Ti, 1986 911 Coupe, 1991 Alfa Romeo 164
    Location
    New York

    I have a friend who also lives in NY and here's what he did... Replaced the cat' with a "test pipe" along with a 90-degree sensor spacer on the rear sensor. Readiness codes set fine and no CEL for several years. I do not condone or warranty these actions will work for you, just passing them along as hearsay.
    Brad 2002 Quattro 1.8T w/ 2.8 B5 5-speed

  3. #3
    Registered Member Four Rings EuroxS4's Avatar
    Join Date
    Jan 24 2010
    AZ Member #
    53856
    My Garage
    2003 Atlas Grey A4 Avant 1.8T 6speed manual quattro,2002 GSXR 600
    Location
    Paramus,NJ USA

    OEM is best or code it out/change the value the ecu needs to see to equal a pass result.Do so at your own discretion.
    VW/Audi Immobilizer removal and immobilizer adapting solutions for any and all VAG Vehicles,Odometer matching, SKC/Pin retrieval services.Located in Northern NJ.For inquries pm for details.

  4. #4
    Veteran Member Four Rings Spike00513's Avatar
    Join Date
    Mar 05 2013
    AZ Member #
    110766
    Location
    CA

    I think I killed mine running rich due to a vacuum leak. (OEM)
    I was told doing this is safe and harmless; apparently not because now I think I have a P0420 CEL for Catalyst Inefficiency, downstream O2 sensor (post-cat)

    and IDK if all states legally allow sales of cats, which affect junkyards (aka cheap prices) if they're trying to stay out of trouble
    There seems to be cleaner-in-a-can type of products that claim to work, but supposedly they actually don't.

    I wonder how to code out the rear O2 in the ECM, and if a smog test can detect if that has been done or not, and how it determines that.
    Because some tunes claim they can code it out as an extra option, but IDK if it will set readiness.
    I know there are certain hand-held scan tools, whether cheap or expensive (though you probably have VCDS), that say if readiness is set. Such as after completing whatever drive cycle is required to set it on the various monitors. (catalyst efficiency, checking of SAI function, 1min cold start warm up on a morning after the car sits for a while, etc.)

    I too am interested in 034 HFC or finding a known-working used OEM replacement for mine, I just don't know if the 034 will pass smog. Supposedly it won't.
    Or if theoretically one can run the 034 and swap in a working OEM one come test time, though that sounds like a PITA labor-wise.

    If in CA, some aftermarket cats seem CARB-approved, while others don't. IDK if there's a difference in quality, or if some just don't want to pay for the testing to get certified. Which technically is required in CA, as smog shops are supposed to look for that stamp plate thing. Not that you're in CA, though.

    IDK if they check for the OEM heat shield and numbers on it. I wonder if that could be cut and welded over an 034 HFC, but that wouldn't address ability or inability to set readiness.
    I hear a J-shaped O2 spacer may make it possible.

    I wonder if 034 labels it as off-road for simplicity, so that it's the owner of the car with the responsibility of figuring out how to make it run right.

    Quote Originally Posted by EuroxS4 View Post
    OEM is best or code it out/change the value the ecu needs to see to equal a pass result.Do so at your own discretion.
    I wonder how the code out/value change in the ECU is done; if VCDS can be used in dumb mode or something, running a different software (not sure what it would even be),
    on Nefmoto forum, was people claiming to tune their own cars using something like that; idk if it's as good as big name tunes such as Motoza, APR, etc.

    Quote Originally Posted by DPDISXR4Ti View Post
    I have a friend who also lives in NY and here's what he did... Replaced the cat' with a "test pipe" along with a 90-degree sensor spacer on the rear sensor. Readiness codes set fine and no CEL for several years. I do not condone or warranty these actions will work for you, just passing them along as hearsay.
    Maybe it's the same J-shaped spacer I'm thinking of? I forget the name of it though
    not sure if this would pass a visual inspection, if the state has it

  5. #5
    Registered Member Four Rings EuroxS4's Avatar
    Join Date
    Jan 24 2010
    AZ Member #
    53856
    My Garage
    2003 Atlas Grey A4 Avant 1.8T 6speed manual quattro,2002 GSXR 600
    Location
    Paramus,NJ USA

    Canít code anything out with vcds.You need to read the bin from ecu and find the address and axis for the catalyst test and end result.You are not coding it out. Simply bringing down the value a bit to get a pass result.

    Software wise you need ida pro or winols and know what your doing.You can also use tuner pro.


    Sent from my iPad using Tapatalk
    VW/Audi Immobilizer removal and immobilizer adapting solutions for any and all VAG Vehicles,Odometer matching, SKC/Pin retrieval services.Located in Northern NJ.For inquries pm for details.

  6. #6
    Veteran Member Three Rings
    Join Date
    Jul 03 2010
    AZ Member #
    61005
    My Garage
    1988 Merkur XR4Ti, 1986 911 Coupe, 1991 Alfa Romeo 164
    Location
    New York

    There are several different types of spacers. Here's one that has a mini cat' right in it...



    You would not pass a visual inspection if such an inspection was done.
    Brad 2002 Quattro 1.8T w/ 2.8 B5 5-speed

  7. #7
    Senior Member Two Rings
    Join Date
    May 05 2014
    AZ Member #
    210984
    Location
    Adelaide Australia

    The 034 HFC is labelled as off road only because in some states the nitrate levels are specified so you would need a cell count higher than 600, the 034 HFC will reduce the emissions and the 2nd O2 sensor may read ok without a spacer and readiness can be set, you may need a spacer if so you could install one before reinstalling. My experience has been that I installed a spacer and angled it 180 degrees to flow and the O2 sensor responded with a too low efficiency MIL, I changed the direction of the spacer to inline with flow and it was all good.



Bookmarks

Posting Permissions

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


    © 2001-2018 Audizine, Audizine.com, and Driverzines.com
    Audizine is an independently owned and operated automotive enthusiast community and news website.
    Audi and the Audi logo(s) are copyright/trademark Audi AG. Audizine is not endorsed by or affiliated with Audi AG.