VW Jetta / Bora MKIV 1998 Euro,1999.5 US -2005
These codes were found with VAG Emulator:
16555 - Fuel Trim; Bank1 - PO171 System Too Lean
16891 - Idle Control System RPM - P0507 - 35-10 - Higher Than Expected. - Intermittent Readiness: 0000 1000
Then car idles higher then drops to normal RPM when driving, It usually stays around 2-3k rpm...