check engine light/error code

[jeep00xj]

hey guys. i got a check engine light the other day and broght my jeep to the car store to have the error code read. and the code that came up was "main catalyst below threshold". does anyone have any idea what the problem could be?

[Ruecifur]

needs a cat or the rear oxygen sensor most likely...how many miles do you have on it?

[XJLI]

needs a cat or the rear oxygen sensor most likely...how many miles do you have on it?

x2

[jeep00xj]

just about 113k maybe a little more. by rear o2 sensor do you mean one of the bottom two? because there are two on the manifold right after the head and then there are two on the lower part of the manifold.

[CumminsJeep]

does your exhaust smell like rotten eggs at all?

[Ruecifur]

it would be a o2 sensor that was after the cat

[jeep00xj]

there are no o2 sensors after the cat. theres two where the manifold is bolted to the head...and then two right before the down pipe. on my 99 there was o2 sensors before and after the cat.

[Ktmracer419]

federal law says you need an 02 after your cat. has the exhaust ever been replaced? maybe you are gettin the code because of a lack of downstream 02

[XJtheXtremeJeep]

im pretty sure i never had one after my cat..... hell i dont even have a cat now

[Ktmracer419]

96 and newer vehicles

op has a 2000

[Ktmracer419]

hell i dont even have a cat now

my biggest jeep related pet peeve right there

[CumminsJeep]

how do you not have a downstream 02 sensor?

[jeep00xj]

i checked. there are no o2 sensors any where after the cat.

[jeep00xj]

what should i do to start tryin to fix my problem becase i have to go through emissions within 30days

[Ktmracer419]

get a downstream 02

someone tampered with your exhaust before and got rid of it. its likely the lack of that 02 is setting your cel