The P0420 code indicates the catalytic converter’s efficiency is below threshold. Start by inspecting upstream and downstream oxygen sensors for faults or contamination.

Mar 23, 2021 · Ever heard of this code? well I got hit with it a while back and it has been coming and going for sometime. Some details about my traverse.. 2010 LT AWD, 258,751 miles. same engine …

Oct 8, 2023 · 2014 2.5L with 100,000 miles showing check engine light. Showing P0420 fault code, (catalytic converter issue), but engine runs very good. No other signs of poor performance. Could …

Mar 15, 2023 · 2019 Chevy Traverse with P0420 Code but with No Check Engine Light catalyst system obd p0420 Jump to Latest 14K views 19 replies 11 participants last post by repairman54 Mar 17, 2025

2016 Chevrolet Sonic LT P0420 Code: Causes Beyond Catalytic Converter Sonic LT often faces oxygen sensor failures and exhaust leaks triggering P0420 codes. The P0420 code indicates catalyst system …

Jun 25, 2025 · I’m hoping you can help me resolve some ongoing issues with my 2015 Chevy Impala LS (Miles: 98,268) that have been confusing me, especially regarding the P0420 code and the battery …

2019 chevy equinox 1.5L 54400 miles has p0299 and p0420 code looking at data during road test vehicle has low power and Mechanic's Assistant chat Customer: I have a 2019 vehicle with a 1.5L …

My code reader shows a P0420 code, which indicates an exhaust leak or a faulty catalytic converter. I recently changed the O2 sensors with genuine GM sensors, and after 200 miles of driving, the check …

The P0420 code indicates low catalytic converter efficiency, often caused by a failing converter or faulty oxygen sensors. Start by inspecting upstream and downstream O2 sensors for damage or …

I have a 2015 chevy Silverado with the 5.3 engine and the check engine light on with this code. P0420 catalyst system