amjadLS430

hi

iam a new member and pretty naive at most of the stuff,u guys have sum pretty serious stuff goin on here and i hope to learn a lot from u guys.

My first query is that if i remove the both the cat converters from the exhaust...

1) Will it affect the exhaust system as a whole?
2) Will there be any problems,if any please specify.
3) Will the rest of the exhaust system suffer,i mean the mufflers and the remaining assy?

On a side note,out here we have no emission tests so that wont be a problem.

thnx

jayclapp

California, the US leader in auto emission reductions, has always had a lower exhaus emission rate that the rest of the US. Are you sure they don't have any emission test requirements? Even in Arizona we have emission tests required to register the car for continued licensing .

warminwisc

Will no catalytic convertors mean you will be polluting the air more? In that is the case, I am east of ya, take it easy on me.

What are yur goals, "cough cough" LOL.

fensterlip

If you're in California, as I am, you most definitely have an emissions test and requirements.
If you modify the system you may not pass and would have to fix it and put it back the way it was and there's no State help to get back in compliance.
Who told you there's no emissions test?
There are Oxygen sensors downstream of the first cats that would complain right away too.

amjadLS430

Thnx for chimin in all of ya...for a second lets jes assume that there were no emission tests which otherwise are pretty tough in Cali but lets jes assume.

Will removing the front cats cause any damage to the exhaust system (mufflers and all) or the car as a whole?

BradTank

Not that I can think of, the exhaust will be louder and it will be a gasoline type smell (like an older car) while you're running. I wouldn't recommend it. And you'll get a "check engine light" on your dash.

The problem is, the cost to remove the cats and fabricate some sort of piping without them is probably going to be close to the same price as just buying an aftermarket cat that pops into place. I've seen them for around $150 a piece that are direct fit models. You're also not going to get any real performance increase

If you're getting a code that the cats need to be replaced and would rather not replace, you can buy an oxygen sensor plug "simulator" where it basically spaces the O2 sensor that's after the cat away from the exhaust flow so it ends the check engine light.

I should give all sorts of disclaimers about in being for "off-road use only" but people usually use them when they've done some performance modifications on the exhaust and don't want the check engine light to be on all the time. In places like California where they have over the top emissions inspections, they'd probably catch you. If I had a "beater" I'd probably do something like that as catalytic converters sometimes just get less efficient with age but still "work".

amjadLS430

Wow BradTank,i havent seen anything about the spacing of the O2 sensors away from the exhaust anywhere and i must say its a great idea.

I got my CATS checked today and found out that i had a gasket which dint properly seal off the joint due to corrosion on the pipes,had it heated,cleaned and beaten to shape and after sum high temp resistant silicone the smell has vanished. As for the CATS,i think they will do for a while coz as u said even if they get old they work.

Where can i find the simulator plug btw?

Thnx

BradTank

You can find them all over the internet, including Ebay. They're usually around $10 to $15, it's just a plug with threads on it.

What that post-catalytic converter (downstream) sensor does is basically a "yes or no" answer if the catalytic converter is working efficiently. If there's as little as a 5% drop in efficiency, it can throw a code and say it needs replacement.

I'm not exactly sure from your post if it was resolved, but if you have an exhaust leak and that's causing a code, get that taken care of as it's dangerous to have that coming into the car.

amjadLS430

Yeah i did have a very corroded exhaust system , especially the mufflers , got them replaced and had the gaskets replaced and the pipes cleaned,i think all that remains is a small leak sumwhere in between the mufflers and the first cats which i havent been able to find out,will prolly lift the car up on the weekend and find out the leak using the age old rag test.Once thats repaired ima space out the O2 sensors if i still get a code.

And yeah as for the smell,it was pretty bad in the beginning but now its all but gone,jes a faint whiff now and then and i am sure once i fix the hidden leak on the Exh assy it will be gone. Donning the mech cap this weekend and lets see what happens.

Thnx