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Can a bad Catalytic Converter destroy a new O2 sensor?

I had a CEL code 134 and I think code 131 as well as a code 420 on my 2003 Acura RSX. So I replaced both front and rear o2 sensors. The codes cleared however the code 420 remained. I haven’t done any diagnostics but a couple other things have caused me to believe my Catalytic converter is bad.

When I was under the car replacing the O2 sensors I noticed that the catalytic converter is extremely rusted at the flanges to the surrounding pipes as well as the heat shield. Also when idling and even on the highway during some spirited driving I’ll notice a sulfur smell. I also noticed some exhaust smells leaking in when idling which is probably due to an exhaust leak from rusty pipes (but that’s another issue).

I bought a replacement catalytic converter but by the time I have it to install it will probably be a month since I replaced the O2 sensors. My question is: Can a bad catalytic converter cause O2 sensors to prematurely fail? Should I take off the new O2 sensors to preserve them while I’m waiting for the parts?

I think you’re getting ahead of yourself. There may be nothing wrong with the catalytic converter, as far as its operation goes. Rust is rust, but that doesn’t mean the cat isn’t working.

A slight sulfer smell now and then is normal (especially if you’re driving in a “spirited” fashion), and sometimes just changing gasoline brands will eliminate the odor.

I think new O2 sensors will improve the operation of the converter, rather than the converter ruining the sensors. I wouldn’t worry about the new sensors. If YOU are worried about the sensors, crawl under the car and install the new cat.

Fresh air getting into your exhaust system through rusty, leaky flanges and pipes can introduce extra oxygen and throw off the sensor signals. Take good care of your engine and your converter can last until it rusts out. They’ve been known to last 300k miles.

A bad converter won’t destroy oxygen sensors, but an exhaust leak under the passenger cabin can destroy your life. Carbon monoxide can put you to sleep without your knowing it’s happening and suddenly…major crash!

And if you begin inhaling that stuff while you’re sitting idling somewhere i can put you to sleep and kill you.

You need to get your exhaust system repaired pronto.