o2 sensor on the catalytic converter

[mitjmac]

This may be a really stupid question, but I'm not a car guy. Where is the o2 Sensor on the Catalytic Converter and what does the Catalytic Converter look like? I'm sure if I found the Cat I could find the sensor.

I recently changed out my o2 Sensor before the Catalytic Converter since I was receiving an error code and the guy at AutoZone said that's what it was.

Low and behold I change the part and bam the engine light comes back on. Go back they retest the engine and this guy says "It's a problem w/ the second o2 sensor, the one on the cat." So I buy the part and I've Googled and searched this form, since it helped me find the location of the other o2 Sensor, but I'm lost with this one.

[CREWZIN]

It's located on the left side of the CAT. No special tools needed.

[Travis2k7]

Pop the hood and follow the exhaust down and you should be able to see the 2nd O2 sensor... you'll have to get it from underneath however.

Did mine the other day after getting P2097 and P0138 codes... was a 10 minute job with a plain old wrench.

There was a little condensation visible when I removed the old one which may have been the reason it was throwing codes.... 48k miles is a bit low from what I've read but at any rate I cleared the codes and all has been well since I changed it.

The majority of my driving is 10 minutes to work, 10 minutes home, rinse repeat which can lead to condensation in the exhaust, or so I've been told.

[mitjmac]

10 min if you know what you are doing. Thanks for the help I was able to get it, but it took me about an hour or so, including time to doctor a burn from hitting the cat. converter since my car wasn't 100% cooled down.

I've noticed a better performance since I've done the change, but I still have a problem when the car will idle. If I have the A/C on and I'm in park/neutral or just at a red light the rpms will drop from 1 to .5 then back up, the A/C will start to blow hot and I've noticed the interior lights will surge . It feels like the car wants to stall out, but it never does. After doing this sometimes it will quit and run normal and the A/C will work just fine.

It only happens when I'm stopped never when I'm driving. Any ideas on this one.

[CREWZIN]

Try cleaning the IAC (Idle Air Controller) located behind and attached to the throttle body.