Posts Tagged: check engine light P0420
Most Common Causes of Catalytic Converter Failure
Top Reasons Catalytic Converters Go Bad Quick Summary The most common causes of catalytic converter failure are • Engine misfires — Misfires cause incomplete combustion that dumps unburned fuel into the exhaust, causing the catalytic converter to foul, overheat, and melt. • Rich fuel mixtures — Leaking fuel injectors or rich fuel mixtures cause extra fuel to enter the exhaust and damage the catalytic converter. • Oil or coolant contamination — Oil burning, internal oil, or coolant leaks can coat the precious metals inside the catalytic converter, rendering them inoperative. … Read More
P0420 Code Causes and Fixes
How to Properly Diagnose a P0420 Code Quick Summary The P0420 code indicates that your vehicle’s catalytic converter is not reducing exhaust emissions as efficiently as the engine computer expects. In most cases, the code means the catalytic converter has failed and must be replaced. However, in some cases, the cause can be due to an exhaust leak that’s skewing the results from the oxygen sensors. Many owners consult the Internet and believe that replacing the oxygen sensors will solve the problem, but that rarely works. If the oxygen sensors … Read More