Advice for Cats

[Cody Forbes]

Tampering with emission control devices is illegal (and a federal offense at that) no matter if it still passes or not, at least in the US. That said, installing catless downpipes is practically its own industry here. Most states only check for codes and readiness bits in the OBDII systems, they don't use tailpipe probes and have private inspection stations with lazy minimum wage kids that don't do a visual inspection. Most chip tuners have "race mode" or "test pipe" software that will disable fault codes associated with the rear oxygen sensors.

-Cody (mobile)

On Nov 20, 2011, at 6:08 PM, gbowles at cansafe.com wrote:

> 
> I'm asking for a friend. He has a 2004 S4 4.2l with 4 cats (as I understand what he said). He is in the process of having the exhaust modified to achieve a sound more in keeping with the beast under the hood. Someone has recommended removing the 2 rear-most cats to get that. This is in addition to replacing the system from the cats back. His question: Is the car likely to pass emission testing if that is done. If so, is it legal. (Passing the test is the bottom line after all.) Any BTDT and/or recommendations appreciated. Thanks.
> 
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Mr. Greville H. Bowles
> Ralston CanSafe
> 525 Glengarry Cres.
> Fergus, Ontario  N1M 2W8
> Phone: (519) 787-1297  Ext. 39
> Fax:   1-800-669-2392
> E-mail:   gbowles at cansafe.com
> www.cansafe.com
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