Volkswagen Jetta check engine light due to low firing piston, requires new engine replacement on Volkswagen Jetta

Some Volkswagen Jetta owners report experiencing issues when the check engine light illuminates, which can be caused by factors such as a faulty oxygen sensor, a loose gas cap, a malfunctioning mass airflow sensor, or problems with the catalytic converter. While these are common triggers, some owners encounter more severe issues, such as a low firing piston that may require a complete engine replacement. This situation indicates a significant internal engine problem that demands immediate professional diagnosis and can lead to costly repairs. It is crucial for owners to address the check engine light promptly to diagnose and resolve the underlying issues, ensuring the vehicle's optimal performance and safety.