Rep Power: 0

If i were to unplug the secondary o2 sensor and not put it after the "cat" on a megan racing "high flow cat". Will the car still run??? Don;t care about the CEL right now.

 
Rep Power: 0

Im not sure if its the First sensor or the secondary sensor, but if it isnt in the pipe, its going to read wayy to much air and no fuel, its going to dump a **** load of fuel in your car. but im not 100% sure.. read what other people say

 
Rep Power: 0

It started. CEL came on of course. Also, there was smoke or exhaust comming from the donut. Is that common in new ones??

 
Rep Power: 0

It will run, just with a CEL. The first O2 is Air/Fuel the second O2 is for emissions. If you want a way to run CEL free follow these instructions.

http://www.corep3.com/phpBB2/viewtopic.php?t=1353

 
Rep Power: 0

The first O2 sensor is used to tell if it is running rich or lean, it is constantley jumping back and forth from rich to lean-this is good,the second is used to tell the condition of the cat it does not verry in voltage very much