What is code p0420 on Lincoln Navigator?

Answer 1

Code P0420 on a Lincoln Navigator indicates that the vehicle's onboard diagnostics have detected a problem with the catalytic converter's efficiency. Specifically, it means that the converter is not functioning as effectively as it should, which can lead to increased emissions. This code can be triggered by issues such as a faulty catalytic converter, exhaust leaks, or problems with the oxygen sensors. It's advisable to have the vehicle inspected to identify and resolve the underlying issue.