Ok this one escapes me....
P0420 Catalyst System, Bank1 Efficiency Below Threshold
Catalyst System Efficiency Below Threshold (Bank 1) . Got that definition from http://www.carsoftwares.com/vwcode.html. Anyone have a clue?
A forum community dedicated to all Volkswagen owners and enthusiasts. Come join the discussion about performance, builds, modifications, classifieds, troubleshooting, maintenance, new releases, and more!