VW Fault Codes 16688 & 16804 Pulled From A VW Golf Diagnostic Check VAG505 - YouTube
P0420 Catalyst system efficiency below threshold bank 1”. Crank no start. Starter fluid changed nothing. Not sure what the code means but my first thought was the catalytic converter? : r/MechanicAdvice
Réparer vos défauts de catalyseur P0420 en suivant notre tuto - Outils OBD Facile
P0420 Oxygen Sensor Fix - YouTube
2004 Jetta P0420 code, every hundred miles | VW Vortex - Volkswagen Forum
313062 Direct Fit Catalytic Converter PO420 for Volkswagen Beetle Golf Jetta | eBay
VW Golf clogged catalytic converter symptoms, causes, and diagnosis
Amazon.com: WATERWICH Compatible with Catalytic Converter Dodge Grand Caravan Chrysler Town & Country 2008 2009 2010 V6 3.3L/3.8L(EPA Compliant) : Automotive
P0420 Code: Catalyst System Efficiency Below Threshold (Bank 1)