2g no cat no cel?

[1995 gst]

Ive been doing plenty of research and getting mixed answers.


I am planning to put a stright pipe in the place of my cat in my 2g, and ive asked weather itle throw a code or make my car run bad and spudder, but ive been getting yes and noes and would like to know the answer.


2g stright pipe without rewire or cel removal just stock removing cat without any other addings will i get a code and if i do will it run bad?

 

[alex209]

I'm runing straight pipe on my 2g I just welded another bung and screwed o2 in no cel light runs fine

 

[007jimmy]

Yes you would probably get a CEL after removal but it might not because of the 95 ECU. My stock 97 ECU tripped the CEL right after I did my exhaust. I then swapped to a 95 ECU and it never came back on, weird stuff... Maybe the 95 ECU is less tolerant??. And no it would not make your car run any worse. Rear o2 only checks to see if you have a properly functioning cat. Performance gains wouldn't be that noticeable although they are there, your exhaust tone could change slightly also.

 

['97boostinGST]

When I had an aftermarket downpipe it never gave me the code, stock 97 ecu.

 

[NHerron]

The first sensor (pre-cat) measures A/F ratio via oxygen content and is seen as a wave (hills up and down on an oscilloscope) this is your performance sensor.

The post-cat 02 sensor wants to see a more leveled out wave indicating the cat is doin' it's thang. Removing the cat will cause a CEL but this is purley for emissions. No problems with performance. However, you keep that CEL light on and it will eventually burn out- now a problem. Solution- install a couple spark plug non-foulers to bring the sensor further away from the exhaust stream. Here's a link-

Install Spark Plug Anti-foulers to Remove SES Light (o2 Sensor Spacer)

 

[Roberti 2G]

I am pretty sure as long as you can get the O2 sensor put in the Test pipe you will be fine. If you dont and just pull the sensor it will throw the CEL. (Had mine bunged in on my first 95 GST)

I owned an EVO IV out in OKinawa and just zip tied the O2 senor to the underside of the car and it never threw the CEL.

From my experience with test pipes/straight pipes as long as that second o2 sensor is getting a air reading it wont throw the code, if it is unplugged it will def throw the code.