Hope this helps!
Info from
http://wiki.ross-tech.com/index.php/Main_Page. - Ross-Tech (Developers of VAG-COM i believe.)
16687/P0303/000771 - Cylinder 3 Misfire Detected
Possible Causes
Ignition system
Fuel injectors
Fuel pressure
Running out of fuel
EVAP canister purge valve
Evaporative emission system
Low compression
Base engine problems
Controle Module damaged
Special Notes
This feature search for engine misfire in a specific cylinder. Most of the time the cause for a misfire is a lack of combustion in a cylinder due to absence of spark, poor fuel metering, or poor compression.
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16524/P0140/000320 - Oxygen (Lambda) Sensor B1 S2: No Activity
Possible Symptoms
Malfunction Indicator Light (MIL) faulty
Possible Causes
Wiring/Connectors from/to Oxygen (Lambda) Sensor Bank 1 Sensor 2 faulty
Oxygen (Lambda) Sensor Bank 1 Sensor 2 faulty
Possible Solutions
Check Wiring/Connectors from/to Oxygen (Lambda) Sensor Bank 1 Sensor 2
Check Oxygen (Lambda) Sensor Bank 1 Sensor 2