Honda Fit 2007 running without O2 sensor

So I am waiting for a new catalytic converters which may be a week or two. In the meantime I have to commute four miles/day for work. Today the car stalled twice and the clogged exhaust is really bad. Can I remove the upstream o2 sensor and drive it around for a few weeks without damaging the car?

What’s the motivation to remove the upstream sensors?

It will allow exhaust flow out so my engine will not keep stalling

Why would removing an O2 sensor allow the exhaust to flow better? Do you mean the O2 sensor is attached to the cat, and you want to remove the cat?

The upstream o2 sensor is before the cat I think and removing it will essentially bypass the clogged cat by having a hole in exhaust pipe where sensor goes


The upstream O2 sensor is what controls the fuel mixture once the engine reaches operating temperature.

If the computer loses the signal from this sensor, the computer will go into a default value for that lost signal. This means the engine will run very rich.

You want to run the engine like this for a few weeks?

Either fix it right, or park it.



Yeah I heard about the default value but didn’t think it would hurt to drive it a few miles a day. Thank you for your input. Guess I won’t try it

Ok, I see what you mean. The problem is with that hole unplugged you’ll have a very, very noisy car. Gonna sound like firecrackers going off as you drive down the street. You may get a ticket w/ that amount of loudness. .

The car could cauch fire with the flaming exhaust flowing from the oxygen sensor hole.

BTW the computer will stay in open loop with the oxygen sensor disconnected.

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what is open loop?

The sensor’s purpose is to obtain nearly perfect ratio of air to fuel for the engine to burn. Closed loop means it uses the O2 sensor reading to adjust the amount of fuel to spray into the engine beyond what it would otherwise spray based on the air flow sensor alone… Open loop means it guesses the amount of fuel to spray based only on the air flow sensor.

In open loop the computer uses the software programming to operate the engine, the oxygen sensor value is not used, same as during start-up when the oxygen sensor is cold.

Thank you for the replies. Can I shake catilytic converter with an electric vibrator sander to loosen it up just a bit for driving for a few weeks? Or maybe bore it out

Have you fixed the root cause of the completely clogged catalytic converter . . . ?! :thinking:

If not . . . :frowning_face:

you said cats. you are changing the manifold warm up cat and the 2nd downstream cat?

It might be possible to remove it, then knock the guts out, and reinstall the shell. That would be illegal though. If you got caught the fine could be substantial. Not something I’d recommend doing. But is it physically possible to do? Probably.

Remember that classic car talk episode . . . the one where the guy hollowed out his cat on the side of the road . . . might have been with a piece of rebar

It’s only illegal remove or tamper with the catalytic converter,
It’s not illegal to drive or operate a vehicle with a removed or tampered with catalytic converter, you won’t pass a smog inspection if your state has them.

Not disagreeing, but it seems a distinction without a difference.

I recall that episode segment, but only vaguely. That’s not Dave from Bemidji is it?