Cat Elimination

[NOTNSUV]

Can the Cat be removed from the exhaust without causing permanent code violations on a '99 4.0L? Haven't had a chance to check for an O2 sensor downstream (since I don't even own an XJ yet). Any way to fool the ECM?
Where I live thereis no emissions testing believe it or not so I'd like to dump that thing.. never cared much for cats; I'm more of a dog lover.

Thanks.

 

[lazyxj]

Can the Cat be removed from the exhaust without causing permanent code violations on a '99 4.0L? Haven't had a chance to check for an O2 sensor downstream (since I don't even own an XJ yet). Any way to fool the ECM?
Where I live thereis no emissions testing believe it or not so I'd like to dump that thing.. never cared much for cats; I'm more of a dog lover.
Thanks.

Other than being a violation of Federal law, there is no problem.
It doesn't matter what state you live in.
Why do you care if you do not own an XJ?
This forum does not advocate the breaking of the law and as an air breathing creature, I do not advocate it either.

 

[sidewaysstarion]

There are a few ways to do it, one is an O2 simulator, but most of them have been banned by the EPA and it's really hit or miss if they will work or not. You could also get your PCM reflashed to turn off the catalyst monitors and the downstream O2 sensor codes, but that would cost your $250-$350 to have done.

But of course you could just run a (good quality) high flow cat and have almost the same power as running straight pipe but not have to worry about codes or breaking federal emissions laws.

Don't believe me?
http://www.importtuner.com/features/0610impp_catalytic_converter_removal/viewall.html

 

[WB9YZU]

These threads are most always an issue, mainly for the reasons stated. Not all States test, and that is mainly a matter of the EPAs interest in an area. For example: Milwaukee and Racine Counties in WI smog test, but in the rest of WI, it is not done. Does that mean that if you do not live in Milwaukee or Racine County you don't have to run a CAT? Nope, it's a federal law. Besides that, it keeps the air cleaner.

Good article, good info in a small package

 

[NOTNSUV]

There are a few ways to do it, one is an O2 simulator, but most of them have been banned by the EPA and it's really hit or miss if they will work or not. You could also get your PCM reflashed to turn off the catalyst monitors and the downstream O2 sensor codes, but that would cost your $250-$350 to have done.

But of course you could just run a (good quality) high flow cat and have almost the same power as running straight pipe but not have to worry about codes or breaking federal emissions laws.

Don't believe me?
http://www.importtuner.com/features/0610impp_catalytic_converter_removal/viewall.html

Thanks for the technical response to a technical question. The XJ I'm buying this weekend has new exhaust on it so it's a non-issue. Just curious as an old hotrodder.