@ptatohed wrote:
@MakingProgress wrote:I have a car question.
I have a 2015 Chevy Sonic with just under 49K miles that is used to drive back and forth to work, and a few errands.
I had a check engine light indicating catalytic converter in 2018 at about 22K. The catalytic converter was replaced under the emissions warranty.
I had the same thing done last month.
I am concerned that simply replacing the converter is treating the symptom and not the cause.
Why would I need to replace a catalytic converter approx ever 3 years?
Please tell us the exact code(s) you are getting.
Code was P0420. I can't find any recalls or specific issues related to 2015 Sonic's, but as Brian mentioned there seemed to be issues with earlier years.
Chevy offers both Federal and California Emissions Control System Warranties. For cars and light-duty trucks, the warranty is eight years or 80,000 miles for the catalytic converter and other parts. Too much un-burned fuel and heat is getting into the converter and frying it. As Brian said. Vehicles do have a O2 sensors. It may be bad and telling the engine to pump more fuel which is frying the converter. Or running rich as us older folks used to say knowing the ole carburetor days. You could smell it. Phew! Too rich and the catalyst can melt down from fuel burning inside the converter.
From the last recall:
On some vehicles, cracking of ceramic components internal to the catalytic converter may occur as a result of higher than anticipated exhaust temperatures. If this occurs, the catalytic converter low efficiency diagnostic will set and the malfunction indicator lamp will illuminate. Correction: Dealers are to reprogram the engine control module with calibrations that prevent higher than expected exhaust temperatures.
@Anonymous wrote:Not what I expected to see on this forum but I can help regardless. Do you have the actual code for the fault ? It will start with a P and have 4 numbers. What state was the car sold in? Post it and if there is other information to go along with it IE any performance issue or anything out of the ordinary. I can give you a direction to proceed between a few different causes and how to troubleshoot and eliminate them until left with the one that is the your problem. The code only gives you a direction to look is often not related to the description for the code. Example a trouble code for an O2 sensor is almost always not the O2 sensor. It's usually something that is upstream from it causing the fault.
Two posts above yours. P0420.
;
;
;
;
;
;
;
;
I'd do the O2 sensors, make sure the ECU had the latest tune from GM flashed into it, have the MAF cleaned, the MAP sensor replaced and probably have the plugs replaced too. If the catalyst still fails...ehhhhhh I have a laptop loaded with the software needed to make the problem "go away". But I am "that guy" and I don't care.
3/3/24
