2003 VW Passat P0421 and P0431 Diagnostic: Causes and Intake System Issues

Model: 2003 VW Passat Fault Code: P0421 Posted: 2009-04-06 21:33

My 2003 Volkswagen Passat is displaying both P0421 and P0431 diagnostic trouble codes. Could these codes be related to a mass air flow (MAF) sensor malfunction or other intake system problems? If not, what are the most likely causes of these codes in a 2003 Passat?