Q: Changed catalytic converter, no lights on dashboard, but codes for catalytic converter & O2 sensor still remain

asked by on

Changed catalytic converter, no lights on dashboard, but codes for catalytic converter & O2 sensor still remain

My car has 129000 miles.
My car has an automatic transmission.

Hi there, thanks for writing in. I am not sure why you changed your catalytic converter. Assuming you had a P0420 code, replacing the catalytic converter should of resolved that code. The codes originally stored need to be cleared. The fact your check engine light remains off tells me, you may have fixed the problem. Try disconnecting the negative battery terminal for at least 2 minutes, reconnect. Start and drive the vehicle for 10-15 miles. Re-check for codes. If a code returns on the first drive cycle (pending code), a problem still exists. The check engine light should come back on (the next drive cycle) if, the fault is recognized by the computer. An exhaust leak before the oxygen sensor will cause O2 sensor and catalytic converter codes. If you are having trouble identifying the fault, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this issue for you, and make or suggest any repairs as needed.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Changed catalytic converter, no lights on dashboard, but codes for catalytic converter & O2 sensor still remain

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Xenon low beam not working

Hello. There is likely an electrical fault on the vehicle side of the wiring harness. Blow fuses or broken wires can plague any electrical system. I recommend having an experienced technician inspect the circuitry concerning the vehicle exterior lighting system....

Q: Transmission doesn't shift, gets stuck in fail safe mode.

Depending on the circumstances, it may in fact be in "fail-safe" mode. When this happens you will normally also have a Check Engine Light on which will usually cause fault codes to be registered in the ECU. When the vehicle...

Q: Heavy gas smell inside car.

It sounds like you have a fuel leak and should not operate your car for safety reasons until you have the issue checked out. This may be the cause of the stalling and starting problems.

Related articles

P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.