How do I know if I have an O2 sensor or catalytic converter?
To the original question: The only way the ECU knows a cat is bad by the readings it get from the O2 sensors. A bad O2 sensor will indicate that the catalytic converter is bad. If the code indicates a bad cat…then further tests need to be run to determine if it’s a bad O2 sensor or a bad cat.
What causes a bad catalytic converter on a Dodge Ram?
Two causes of catalytic converter problems are heat produced by engine misfiring and backpressures that trap exhaust in front of the catalyst. Bad RAM catalytic converters lead to raised carbon emission levels and a ruined exhaust system.
What does the sensor on the catalytic converter do?
The downstream oxygen sensor, on the other hand, should show very little movement. It’s testing the catalytic converter to see if it’s storing oxygen during rich events and then using the oxygen during lean events.
What should the OBDII reading be on a bad catalytic converter?
The ECM would interpret that as a bad catalytic converter. In that case, your OBDII scanner should be reading a lean 0.1v reading from the downstream sensor. You can add propane fuel to the exhaust to force the reading up to prove that the downstream sensor is good.
Can a bad catalytic converter cause an oxygen sensor to go bad?
In 99.5% of the cases, this code means that the catalytic converter itself is bad and must be replaced. However, I see questions all the time on auto forums asking if a new oxygen sensor will fix the problem.
What is the catalytic converter code on a Dodge Ram?
Your Dodge Ram leaves the factory with a catalytic converter. It can run into problems over the normal life of the vehicle, and is often accompanied by OBDII code P0420. Below we’ll cover the location, price, and symptoms of a bad torque converter in your Ram.
The downstream oxygen sensor, on the other hand, should show very little movement. It’s testing the catalytic converter to see if it’s storing oxygen during rich events and then using the oxygen during lean events.
Can a lazy oxygen sensor cause a catalytic converter problem?
You may need to fix other engine problems in order to solve your catalytic converter problem. A lazy oxygen sensor might falsely indicate a catalytic converter problem, yet not set a DTC for itself. A technician can determine if the sensor is responding as it should.
The ECM would interpret that as a bad catalytic converter. In that case, your OBDII scanner should be reading a lean 0.1v reading from the downstream sensor. You can add propane fuel to the exhaust to force the reading up to prove that the downstream sensor is good.