2nd O2 sensor?

[SaintlyCharBoy]

i installed my hotshot 2 days ago, it had a fitting for a second sensor, which would, on the stock piping, follow the cat.  

they sent me the wrong adaptor for the sensor, so
1 there is a hole in my header, about 12mm around and my car is hella loud, has 0 back pressure, poor flow, and backfires a lot

2 even though the sensor is not "sensing" any of my exhaust due to my inability to install it, the car is running fine...

any theories?
wha tis the sensor there for any ways?

i'm kind of figuring that is it just taking an O2 readig from the ambient air, so it's working, but not doing it's true intended job... and thus far i've been lucky

thanks for any insight
Sean

[rubbersidedown]

my guess is that maybe its for an exhaust gas temperature sensor.

[Racer X]

i going to assume that you have an obd2 car (95+) the second o2 is there only to tell you computer if your cat is working right. if you had a v8 four sensors <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/crazy.gif" border="0" valign="absmiddle" alt=':crazy:'> gotta love our tree hugging government leaving it out will soon cause a check engine light but other than that will not affect performance at all.

[bbp]

I would not drvie the car too much missing that plug. &nbsp;My Hotshot header had 2 ports, one for the egr (plugged) and the other for an O2 sensor. &nbsp;They should sent you a plug for the second sensor, running the car with a hole in the exhaust that close to the head could burn a valve.

Otherwise you should be fine except for the check engine light. &nbsp;It will only trip the light if you are at anything except wide open throttle. &nbsp;So, if you don't like the light, drive around with the throttle mashed to the florr &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'>