HFC and Emissions???

[WantaA4]

Alright... So let start off with, I have searched but only found old stuff and found nothing on B8's... Only B6's. I want a HFC for my B8 but I wanted to know if other guys with a HFC were able to pass emissions? I don't have APR so I know I will need the spacer so I don't throw CEL's... Any feedback would be great from guys who have passed emissions w/ HFC's.

[MiracleWhips]

Keep in mind each state's laws and tests are different.

While you may pass the computer, you may not pass the visual if/when performed.

[gdawg'05a4]

I have APR's Stg 2 w/ the turbo-back exhaust. There are two versions of Stg 2, a test pipe file and non-test pipe file. The test pipe file will disable the Cat and O2 monitors so readiness will never be set and always at "Incomplete". You won't get a CEL either for catalytic efficiency. I believe most if not all states check for readiness codes. I originally had the test pipe file but then re-flashed to the non-test pipe file so that I could pass emissions (MA checks for readiness). I needed to install a spacer for the HFC otherwise the CEL would be triggered.

[Hugh@EuropaParts]

HFC's are hit/miss as far as the CEL is concerned... usually a spacer does the trick. Stage 2 software will definitely solve any HFC related CEL's...

034Motorsport High Flow Catalytic Converter (A4/ B8, 2.0T) (http://www.europaparts.com/034motorsport-high-flow-catalytic-converter-a4-a5-b8-2-0t.html)

http://media.europaparts.com/catalog/product/cache/1/image/cd6085ca2ccd08373d4b6de971808fb4/0/3/034motorsport-hfc-b8-2-0t.jpg (http://www.europaparts.com/034motorsport-high-flow-catalytic-converter-a4-a5-b8-2-0t.html)

This 034Motorsport high-flow catalytic converter for Audi A4/A5 B8 is designed to replace the restrictive OE catalytic converter, and allow for quicker spool while increasing horsepower and torque throughout the powerband.

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Complete drop-in upgrade; will bolt up to any stock/stock-fit turbo and stock/stock-fit exhaust. Professionally assembled by 034Motorsport, TIG-welded and backpurged.


Full 304 stainless construction.
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CNC machined flanges.
Factory correct oxygen sensor and exhaust hanger placement.
Dyno proven horsepower and torque gains!
Smog tested.



Gains of over 24WTQ and 27WHP have beens seen on 034Motorsport's dyno on stock turbo tunes.

Direct bolt-in for OEM cat-back exhaust, or aftermarket cat-back exhaust systems designed to fit with the OEM catalytic converter. Will fit Quattro and FWD B8 Audi A4/A5 2.0 TFSI models equipped with manual, Tiptronic, or CVT transmissions.

Please Note: Installation gasket and hardware kit and oxygen sensor spacer available as options below.

Gasket & Hardware Kit - We have pieced together all of the necessary parts to make swapping out your factory catalytic converter a breeze. This kit includes turbo outlet and cat-to-midpipe gaskets, as well as all necessary nuts and bolts for a complete install.

Oxygen Sensor Spacer - This spaces out the secondary (rear) O2 sensor to remove MIL or CEL issues caused by removing the factory catalytic converter. Professionally manufactured from stainless steel, not cobbled together by hand like some other products on the market. Spacer will add approximately 1.7" to the height of the sensor. 034Motorsport oxygen sensor spacers feature a flare seal seat, so no sealing washer or gasket is required.

http://media.europaparts.com/catalog/product/cache/1/image/cd6085ca2ccd08373d4b6de971808fb4/0/3/034_b8_hfc_gains.jpg (http://www.europaparts.com/034motorsport-high-flow-catalytic-converter-a4-a5-b8-2-0t.html)

[nikatrel]

Keep in mind the CEL spacer might not work, it didn't work for me.

[gdawg'05a4]

HFC's are hit/miss as far as the CEL is concerned... usually a spacer does the trick. Stage 2 software will definitely solve any HFC related CEL's...


If the Stage 2 software disables the monitoring so that a CEL (usually called a "test pipe file") won't show up then yes it will solve HFC related CELs. However keep in mind that a lot of states check for readiness and if the Cat and/or O2 readiness codes are not set then it may lead to emissions test failure. YMMV.

[gdawg'05a4]

Keep in mind the CEL spacer might not work, it didn't work for me.

What type of spacer was it? A regular one that just extends the length from the bung to the O2 or a angle block? This is the one I installed on mine and works:

http://t3.gstatic.com/images?q=tbn:ANd9GcQPKgsRDjp46vS7JtOn4bFuh5pHaCGai M50y6jBVJy--j8kajSzWgnH_MhS

[WantaA4]

Keep in mind the CEL spacer might not work, it didn't work for me.
Hey noticed you were in VA.... What spacer did you get?

[WantaA4]

What type of spacer was it? A regular one that just extends the length from the bung to the O2 or a angle block? This is the one I installed on mine and works:

http://t3.gstatic.com/images?q=tbn:ANd9GcQPKgsRDjp46vS7JtOn4bFuh5pHaCGai M50y6jBVJy--j8kajSzWgnH_MhS
I don't have APR so I would need the spacer. Which one is the one in this pic?

[WantaA4]

Hugh.... that is actually the HFC I am looking at getting. Are those dyno numbers with an exhaust?

[rippin'av]

Alright... So let start off with, I have searched but only found old stuff and found nothing on B8's... Only B6's. I want a HFC for my B8 but I wanted to know if other guys with a HFC were able to pass emissions? I don't have APR so I know I will need the spacer so I don't throw CEL's... Any feedback would be great from guys who have passed emissions w/ HFC's.

Hmmm...this took me 5 seconds to find...

http://www.audizine.com/forum/showthread.php/410089-APR-stage-2-and-smog-test-does-not-go-together?highlight=Stg+2+smog

http://www.audizine.com/forum/showthread.php/434434-Test-pipe-and-O2-spacer-with-catalyst?highlight=CEL+spacer

http://www.audizine.com/forum/showthread.php/429190-APR-Stage-II-Texas-Emissions-Failed-Test?highlight=CEL+spacer

http://www.audizine.com/forum/showthread.php/419413-o2-Spacer-options?highlight=CEL+spacer

http://www.audizine.com/forum/showthread.php/379262-034-HFC-CEL-side-up?highlight=CEL+spacer


Some good info in there. You won't pass CA smog with CEL from the HFC. Even Stg. 2 (testpipe file) will not pass CA smog. You need to try your luck with the right spacer and "non-testpipe file" like others have stated and hope your guy doesn't look too closely for the inspection. Its pretty obvious that the 034 HFC is not stock so it might need a little persuasion .

Good luck.

FWIW, when I had to smog my car I had to flash back to APR Stg 1 and remove my HFC. Its still sitting in my garage until I decide what to do with it. I might go back to Stg. 2 w/ HFC because I really miss the power and just go with a spacer. Its really noticeable with the HFC alone BTW...but each time I will need to smog I'll be worrying about passing...I hate dealing/hasseling with sh!t like that.

Cheers, AV

[WantaA4]

Well you know to use the search function better than me.... Thanks 4 pointing it out.. I put in HFC emissions.. And only got old stuff sorry.... But thanks for your professional search

[WantaA4]

Well after more research.... I think i'm just going to go with the exhaust... I don't feel like pulling the HFC off every time I need emissions. Thanks for the insight fellows

[inNout]

What type of spacer was it? A regular one that just extends the length from the bung to the O2 or a angle block? This is the one I installed on mine and works:

http://t3.gstatic.com/images?q=tbn:ANd9GcQPKgsRDjp46vS7JtOn4bFuh5pHaCGai M50y6jBVJy--j8kajSzWgnH_MhS


More info on this spacer?

[TCHUN003]

You could get a HFC, switch to stage 1 right before you go to get smogged, and clear the code with a VAG (the CEL should go away for enough time for you to get your smog done). This is what I plan on doing since I have the SPS program switcher for my REVO software.

[rippin'av]

You could get a HFC, switch to stage 1 right before you go to get smogged, and clear the code with a VAG (the CEL should go away for enough time for you to get your smog done). This is what I plan on doing since I have the SPS program switcher for my REVO software.

Not sure how the REVO software works but if you can switch back to stage 1 then it could work? go for it and report back TCHUN003! [cool]

I've seen so many people with HFC in CA that I'm sure the visual isn't crazy to pass. If its possible in CA it should be possible in the other strict smog states I'm assuming. I do know that people have had success with the stratoshpere spacer so I'll probably end up trying that one day. APR software will not allow you to switch from Stage 1/2 for some reason. The best bet if you have APR would be HFC w/ a proven spacer, then either stock programing or APR stage 1/2 (any version that allows CEL) ...but maybe the REVO software is cool too with the ability to switch back to stage 1/2 which sounds like a great feature.

[gdawg'05a4]

APR software will not allow you to switch from Stage 1/2 for some reason. The best bet if you have APR would be HFC w/ a proven spacer, then either stock programing or APR stage 1/2 (any version that allows CEL) ...but maybe the REVO software is cool too with the ability to switch back to stage 1/2 which sounds like a great feature.

Can you elaborate on what you mean by this? I originally was flashed with the Stg II test-pipe file and was able to be reflashed to the Stg II non-test pipe file. Are you referring to going from Stg II to I? Even then I don't see why you cannot, it's just over-writing what software is on there already from the same tuner.


More info on this spacer?

The best bet if you have APR would be HFC w/ a proven spacer, then either stock programing or APR stage 1/2 (any version that allows CEL) ...

APR fullback + Stg II non-test pipe file + Wayne (named after the guy who came up with it) angle block spacer (the one I showed above) = no codes or CEL. Google it and you'll find plenty of reviews on his spacer. You can also email him directly for one...I think it's $38. Wayne Schmidt (wayne92slc@yahoo.com).

[rippin'av]

Can you elaborate on what you mean by this? I originally was flashed with the Stg II test-pipe file and was able to be reflashed to the Stg II non-test pipe file. Are you referring to going from Stg II to I? Even then I don't see why you cannot, it's just over-writing what software is on there already from the same tuner.




APR fullback + Stg II non-test pipe file + Wayne (named after the guy who came up with it) angle block spacer (the one I showed above) = no codes or CEL. Google it and you'll find plenty of reviews on his spacer. You can also email him directly for one...I think it's $38. Wayne Schmidt (wayne92slc@yahoo.com).

Yes, I meant that once you have the Stage 2 flash you can't switch (with your cruise control buttons) from Stage 1 to Stage 2 tunes.

[V1Rotate]

Im in VA with a HFC and no CEL with a 90 degree spacer from Stratmosphere... I have the Stasis tune with both o2 sensors enabled, and can pass smog with no issues. Go for it.

[TCHUN003]

With REVO, you can switch from stage 2 to stock with the SPS switcher. This is what I did with my APR B6 4 months ago, but I had to go back to a dealer to switch it to stage 1 because APR's program does not allow you to do this.

[WantaA4]

Im in VA with a HFC and no CEL with a 90 degree spacer from Stratmosphere... I have the Stasis tune with both o2 sensors enabled, and can pass smog with no issues. Go for it.
You might have changed my mind.... thanks

[maga4]

With REVO, you can switch from stage 2 to stock with the SPS switcher. This is what I did with my APR B6 4 months ago, but I had to go back to a dealer to switch it to stage 1 because APR's program does not allow you to do this.

APRs software let's you do this? Can do it with the cruise control buttons.

[TCHUN003]

APRs software let's you do this? Can do it with the cruise control buttons.

No, APR does not let you do this, which is why i had to go back to the dealer to switch it to stage 1. I do have the ability to do this with REVO though.

[maga4]

Got it. Thought you meant stage 2 back to stock like you said with revo above.

Does this mean that if you have a stage 2 file/hfc/test pipe file with apr and you switch it back to stock, you will have the sensor turned off too?

[vdubjetta02]

HFC's fail typically after only 1-2 years..... I have ran everything from an APR to an 034.... It always passes emissions the first year and by the 2nd year it fails.....

Now I just go Catless & swap back to stock the day of emissions.....

[TCHUN003]

Got it. Thought you meant stage 2 back to stock like you said with revo above.

Does this mean that if you have a stage 2 file/hfc/test pipe file with apr and you switch it back to stock, you will have the sensor turned off too?

I had a stage 2+ and flashed it to 1+...you could flash it to stock to pass smog too. Just remember to clear all CELs before you get your smog.

[A4 Centaur]

Just ordered mine today. Will report what happens after install and post some sound clips.

Going to Magnaflow 12" cans out back, leaving stock resonators in place for now.