I just bought a 98 ls1 car and its reading 2 o2 codes with the engine light on.. I ordered 2 sims should I order 1 more and sim out all 3 or is that a bad idea should I have atleast the one behind the cat?

 

02 sims only go on the back two spots.
your car uses the front two

 

2 sims for the rear sensors is all you need.

But, you could just go to a shop and delete the codes if you still have cats.

Or, better yet, get a tuner and delete the codes, plus add some HP.

 

The exhaust on the car comes back in the y with a cat on one side then it connects up and is straight piped the rest of the way back.. I was looking and I only saw a o2 behind the cat on one side I didnt c a 4th nore the wires for it.. So should I look and hopefully find the 4th and sim the the 2 rears out?And replace the front 2 with new o2 sensors?

 

You should have 2 cats, each with an O2 in front and behind it. You can get sims for the rears but not the fronts.

 

(rears) one right behind one cat, and the other is farther down the line
(fronts) are right in front of the cats

 

Yeah the front ones are right after the manifolds on the down pipes...I found a 3rd right behind the cat and the 4th? Im going to have to wait for it to cool off some outsdie before I go searching for it .. Thanks guys for the inputs..

 

its farther down almost near the tranny mount

 

? Thats the one I thought was the 3rd? The one after my cat is next to the tranny mount.... The driver side one is right after the manifold and the passenger side one is right after the canister that is right after the manifold... The passenger side of the y pipe doesnt have a cat on it nore a 02 sensor.. I plan on here real soon buying some headers and a tsp xpipe... Im just trying to get everything else lined out before then all the bugs..

 

Are all the o2 sensors wired into the lower tranny harness? or is the forthest one from a differnt location.