Can a bad O2 sensor be something else?

Can a bad O2 sensor be something else?

Mechanic ran diagnostic again and said it still is showing bad o2 sensor but since he replaced it the problem must be a catalytic converter that is plugging up and should be replaced. Since replacing a converter is costly I want to make sure this is the problem. My question; could this be something else or does the converter need to be replaced?

When do I need to replace the oxygen sensor?

If the sensor after the catalytic converter shows minimal changes from the reading on the first oxygen sensor, it is a sign that the catalytic converter is not working properly. Modern vehicles with V-6 or V-8 engines could have as many as four O2 sensors — one located in each cylinder bank and one after each catalytic converter.

When to reset the ECU after changing an O2 sensor?

Sometimes an O2 sensor fails, and you need to replace it. Once you’ve replaced your vehicle’s O2 sensor, you’ll need to reset the ECU so it can properly gather information from the new O2 sensor.

Where are the oxygen sensors in a car?

Modern vehicles with V-6 or V-8 engines could have as many as four O2 sensors — one located in each cylinder bank and one after each catalytic converter. If either the oxygen sensor in the cylinder block or the one for the catalytic converter fails, your vehicle could experience serious engine problems.

When to get an oxygen sensor replaced in your car?

As soon as you notice your Check Engine Light, poor gas mileage, or an irregular engine idle, book an appointment to have your oxygen sensor replaced. This will ensure your vehicle is running smoothly, efficiently, and will help prolong the life of your engine.

What causes an oxygen sensor to set trouble code?

A leaky exhaust pipe obviously can let exhaust gases out of the pipe at the leak. But air can also be sucked into the pipe at the same leak. If that leak is upstream of the sensor, it will see the extra oxygen and set a trouble code. This is a costly repair, but common with a p0420 code.

What does it mean when your oxygen sensor says P0420?

Oxygen sensors are only a part of a greater system, meaning if the p0420 code (or p0141, or p0135) is thrown, that doesn’t necessarily indicate the oxygen sensors need replacement. Rather, there could be something else in that system does that’s causing the oxygen sensors to appear faulty.