How do I fix a 420 code
420 is a catalytic converter afficiency code. It could cause by many problems: bed fuel, old spark plugs, sensor wiring connection. I would replace plugs and fill with premium fuel, turn off the code and drive to see if it comes back. If it does, stop by any muffler shop and have them run cleaner threw your system, it may give you 5 to 6 month driving but sooner or later you will need new cat for your car. Hope it helps.
Posted on Apr 30, 2014
Oct 12, 2014 | 2004 Lincoln Aviator
Sep 12, 2014 | 1998 Chevrolet Astro
Sep 12, 2014 | Cars & Trucks
Apr 19, 2012 | 1991 Mercedes-Benz 420
Feb 19, 2011 | Toyota Camry Cars & Trucks
Aug 21, 2010 | 2001 Volkswagen Golf
Feb 15, 2010 | 2005 Chevrolet Colorado
Nov 18, 2009 | 2000 Chevrolet Cavalier
Sep 14, 2009 | 1996 Plymouth Breeze
Jul 28, 2009 | 1999 GMC Sierra
140 people viewed this question
Usually answered in minutes!
×