Join Date: Apr 2007
Location: Gainesville, VA and Ypsilanti, MI
I suspect that you don't have an oxygen sensor issue, but a true cat issue (at 230K miles, no big surprise). The sensors would throw different codes. So, if you decide to replace the O2 sensors (which don't have to be replaced in pairs by the way) the code might not go away.
As to the O2 sensors if you should decide to go that route: 180 for a sensor without labor is stealing..... The front ones you can do yourself easily. All you need is a special socket that has a slit in it on the side for the wires. When/if you replace them, run the car first for a minute or so to heat up the exhaust system. That will make replacement easier (when cold, their are in there TIGHT). The rear (downstream) ones are a bigger pain to get to. On the passenger side, you best try to get to it over the top, but remove at least part of the air cleaner system. On the driver side, you can get to it from underneath....(on the passenger side, the transmission is in the way). Online, true, genuine OEM sensors for your model year are MUCH cheaper, even with the connector already attached. Even if you go to a dealership's parts department, you will get them cheaper.... let me dig out part numbers and stuff and get back with you in about an hour... There is also another very good thread about O2 sensors I will dig out, that gives you all kinds of info on them.... Again though: I don't think it is the O2 sensors, but the cats themselves that are going bad....
2002 Intrepid R/T, silver - 141,xxx miles
1979 Magnum XE, scarlett and grey (OSU) - 138,xxx miles
R.I.P. Kyle G Meyer - only the good die young