Check Engine Light On

[rlawrence]

Results - Cat performing below threshold. Does this mean I need to replace the Catalyic converter? or would anyone sugest replacing the oxygen sensors first? Everything on this car is original.

This is a 2004 Corolla S with 230,000 miles. Runs like a top.

[arabianobsession]

Holy crap that's a lot of miles.
Replace the cat.......and your O2 sensors....at this mileage you might as well do both

[mikered30]

At that mileage it is probably the cat. Can you have someone back probe both oxygen sensors to check them before going broke getting a new cat.