About to gut my precats

[mistermoonpie]

Hey guys. I'm gonna gut my precats, but I seem to remember hearing something a while ago about like needing 02 sensors, otherwise Im gonna throw a CEL? I was reading the how-to on 3si, and i didnt see anything about needing to buy any parts or anything. Does anyone know something I don't before I go hack away at my precats?

[Crackhedbob341]

You need an O2 simulator. Your primary (first) sensor is in your O2 housing and sends a signal to your ECU telling it the saturation of oxygen in your exhaust. That is a factor which controls your A/F ratio. (Too much oxygen, means it you will get more fuel. Not enough, and the ECU leans it out). Your secondary O2 sensor is after your precat. It works in the same way, detecting the amount of oxygen in your exhaust AFTER the precat, or after the fumes are catalyzed. They are only there to make sure your precats are in working order.

Once you gut your precats, the normal voltage the secondary O2 sensor normally sends to the ECU obviously changes, which in turn throws the check engine light because the ECU thinks your need to replace your precats because there is something wrong with them. You resolve this problem by using the O2 simulator, which sort of piggybacks your secondary O2 sensor, and alters the signal sent to the ECU so it thinks that the precats are still there. I would trust 3SX, I bought mine from them.

Here are two guides I made on Florida3S, look at them and learn from them. Please, that is why I made them.

Quick note: You only need to get the O2 simulator if you first of all have precats (All TT models, and Cali-Spec 3S's).

Quick note 2: You do not need an O2 simulator if your car is a hybrid.. 94-95 3S.

http://florida3s.com/forum/showthread.php?t=10842 <---- Clicky Clicky

http://florida3s.com/forum/showthread.php?t=11481 <---- Clickity Click

Hope this helps.

http://www.3sx.com/store/comersus_vi...?idProduct=769

[95DodgeAvenger95]

get ready to get shit and metal shavings in ur eyes if u do the rear with it still on the car and ull be sore after hammering and drilling and shit at it from under the car, have fun =)

[Crackhedbob341]

Yeah for real ^^^. Get a mask to keep asbestos out of your lungs, like what surgeons use. The eyes was the worst part. Get goggles that completely cover your eyes, like the old fashioned scuba mask that covered your eyes and nose and was just an oval piece of plastic. You'll also need a LONG THIN pair of needle nose pliers for the mesh rings. I wrestled with the damn rear one in the top for 15 minutes after it was all clean before it let go. It was like 3 AM and I just wanted to get home and shower. Get a long .5 or 1 inch chisel and a hammer. You'll be doing the rear for like 3-4 hours wondering when you'll hit the top, along with trying to not hit or drill the O2 sensor.