My mechanic recently told me the following regarding check engine light codes:
Checked DME Fault Memory, fault codes 12, 203, stored in memory. Performed related test modules for faults stored as per GTI (BMW Diagnostic Analyzer).
1) Fault Code 12, Oxygen Sensor 2 open circuit, currently not present
2) Fault Code 203, Oxygen Sensor Control 2; mixture at oxygen sensor is too rich. Currently not present, traced to a faulty PCV valve, recommend replacing PCV valve cover.
How easy is it for me to replace the PCV valve? I assume the is the problem and not a faulty oxygen sensor?