on a 05 rsx-s, had dcrh and did a defouler and still have check light on after resetting battery. assuming its a bad o2 sensor. with the o2 sensor checklight on, does it mess up on any engine performance?

 

from my experience with bad O2 Sensors it doesnt have a hard affect on your motor but it wont let you wont be able to pass smog and it you wont be able to know if anything else on your Type-S is malfunctioning

 

Anything that affects your A/F ratio will have an effect on your vehicle's performance. In your case a negative one. Your car's computer is telling it to run rich to protect your motor because the sensors can't give the ECU a correct reading.

 

true.. but the first o2 sensor reads A/F. The second one only reads catalytic converter. So his check engine light is most likely from the second o2 and the car thinks the cat is bad. Shouldn't affect air/fuel. Right?

 

Hmm... beats me

OP, get your codes read one more time and see if it says bank "1" or bank "2". Honestly I'm not sure if one is more important than the other but either way, I would want it fixed haha.

 

yeah still wondering if reading error on the catalytic converter will trick ecu to run richer. i'm just getting code for the catalytic converter o2.