removing cats

[Semperfiws6]

my check engine light just came on. the codes say its either an o2 sensor, or the catalytic converter (bank 2) if i remove the converters, and therefore the o2 sensor, will the check engine light stay/go on? anybody know? 98 t/a ws6.

[barryTA]

Yes the light will stay on unless you install o2 sims

[Semperfiws6]

whats an o2 sim?

[Mykota00]

it replaces your o2 and it reverses the code to make it look like you have cats

[barryTA]

there called o2 simulaters they plug into the rear o2 sensors when removing
the cats. they tell your cars computer that the cats are there and working fine.

[MikeSomething]

Now remove your EGR and AIR and you'll have to tune em out to kill that SES light.

[Mykota00]

what does removing your egr do? are there any pros or cons?

[barryTA]

wait a minute all you are trying to do is get rid of your check engine light
right ?

[Semperfiws6]

yes.

[Semperfiws6]

yes, but i want the problem fixed and i dont know how to tell if its the o2 sensor or the cat. i figured i would start with the o2 sensor. the code is not specific.

[barryTA]

if your cats were bad or you rear o2 sensor are bad all you have to do is
install o2 sims.

[barryTA]

unless its your front o2 sims that are bad

[Semperfiws6]

but if its my cat, wont that eventually effect driveability?

[barryTA]

if its your cats the check engine light wont go away

[Mykota00]

i had a firebird v6 with a blown internal cat and it took me 10 minutes to hit 60mph so i think in some cases it would

[barryTA]

if the light goes away after you fix the o2's then you know the cats are fine

[Mykota00]

your front o2's should be fine if your cat went bad it might make the year o2's go bad so i would replace cats and rear o2's

[123456speed]

I have true duals with no cats and my car runs perfect.... how would not having cats effect the car that much?? and my check engine light isn't always on.. it comes and goes as it pleases.. took it to the dealer and they always tell me "if you would return the exhaust to factory settings the light wouldn't come on.." haha but that wouldn't be as cool!!!

[LS1Formula01]

Cats are just an emissions control device, they are not necessary in the operation of an internal combustion engine people. It is on bank two and the only way the computer senses a problem is through sensors, it doesn't know the actual condition of the cat until the exhaust gases hit the downstream o2 sensor (the one right behind the cat). If you take the car to somebody who can tune your car or pay about 80 bucks for some o2 sims, the light will go off, I had my cats taken out and had a guy tune the rear o2 sims to read a fixed reading.

[LS1Formula01]

Just remember that a check engine light doesn't mean the car is going to self destruct. Just run the codes, and it generally comes out to be a faulty sensor or something to that extent.