How to reset the catalytic converter and 02 sensor?

O2 sensors are located in the exhaust system, before and after the catalytic converter, (Cat).
Sensor 1, (Upstream sensor), is before the catalytic converter, often positioned in the exhaust manifold or in the down pipe attached to the manifold.
Sensor 2, (Downstream sensor), is positioned under the vehicle after the catalytic converter. They usually stick out at 90 degrees to the exhaust and can be a real pain in the tailbone to get out.

Usually these are located on the exhaust manifold or just below the exhaust manifold and you should be able to see it in the engine bay. On V6 engines there will be one sensor on each of the 2 exhaust banks.
You will probably need to remove the engine cover to see the sensors on your exhaust.

If someone told you to replace these because you got a particular fault code I would be wary. A decent scan tool and basic diagnostics can show if the 02 sensor is working or not. Some faults often blamed on an 02 sensor are not due to faulty sensors.

O2 sensors are all screwed into exhaust system there are from 1(older) to 4 (modern 2 exhaust circuits). The uppers are located before the catalytic converter and the lowers after the catalytic converter. They generally need to be replaced between 50-100,00miles as recommended by the manufacturer.

Yes, the leaking flex pipe could cause this code. You need to fix that, clear the code and re test. BUT: This vehicle has had issues with the catalytic converters coming apart and ruining the engine. It can suck catalytic converter pieces into the engine. When the converter is removed, visually inspect for damage.

The cat. Converter is for emission for car inspections...if or state doesn't require it then ...no..but from what I know..being a state inspector myself is they r required...
No sensors in converter itself but u should have a 02 sensor before it and after....sometimes they can be on it but not in it

What was the exact code? The O2 sensor after the Catalytic Converter, or Rear O2 Sensor, could be faulty which would cause the computer to think the Catalytic Converter is not working efficiently. The code can be reset at the auto parts store with the same code reader they used the first time. P0420 is the most commonly thrown OBDII code pertaining to catalytic converter efficiency below threshold. I would replace the O2 sensor after the Catalytic Converter and reset the computer to see if the code comes back. If it comes back you may have a bad catalytic converter, exhaust leak, damaged exhaust pipes, damaged O2 sensor wiring/connectors, plugged catalytic converter, etc.

I’m happy to help further over the phone at https://www.6ya.com/expert/jeremy_69f3cc28d95bf514

• Up-stream sensor (located before catalytic converter)
• Left up-stream sensor (located before catalytic converter)
• Left down-stream sensor (located after catalytic converter)
• Right up-stream sensor (located before catalytic converter)
• Right down-stream sensor (located after catalytic converter)

4 sensors total.

Code P0433 is Heated Catalyst Efficiency Below Threshold (Bank 2)

Basically there's a problem with the readings of the 02 sensors. The first one should fluctuate in its reading while the downflow one should remain fairly constant.

Some suggested steps for troubleshooting a P0433 code include:

* Check for exhaust leaks at the manifold, pipes, catalytic converter. Repair as required.
* Use a scope to diagnose the oxygen sensor operation (Tip: The oxygen sensor in front of the catalytic converter normally has a fluctuating waveform. The waveform of the sensor behind the converter should be more steady).
* Inspect the downstream heated oxygen sensor (HO2), replace if necessary
* Replace the catalytic converter

P0455 is an EVAP system leak. Inspect your fuel system including all hoses, canisters, and filler neck for leaks/damage. A common cause of this code if no leaks are found is the EVAP vent solenoid. Once I replaced that solenoid on my car the code was gone.

The best way is to replace the cat, it could be the 02 sensor but would suggest you replace the cat from a aftermarket car parts store, they will coast about $80.00 tops and I would replace the 02 sensor as well after 8 years the 02 sensors get what is called lazy 02 syndrome and does not cycle fast enough to keep up with the changing fuel needs of the computer. If you replace the 02 sensor you will get better fuel mileage and will not risk plugging up the cat in the near future, And if you had any missing in the engine you have damaged the cat so replace it so you don't have to much back pressure, you can check the cat with a temp probe to see if it is functioning or not to be sure, but for a total of $100.00 bucks you will save yourself time and effort in the years to come, and itf the cat plugs up it won't run so change them both. hope this helps.

P0420 Catalyst System Efficiency Below Threshold (Bank 1)

There is one 02 sensor in front of the catalytic converter (called upstream), and one behind it (downstream). When the engine is warmed up and running normally the upstream oxygen sensor reading fluctuates and the downstream one is fairly steady. In the case where both readings are fairly steady, a P0420 check engine light code is set.

Possible Causes:
Oxygen (O2) sensor not working correctly
Damaged or leaking exhuast (pipe, manifold, catalytic converter)
Damaged catalytic converter