Issues with the PCV Valves on the Aston Martin DB9 are common, and lead to an oil buildup in the Air Intake Plenums.

This collection of articles covers all you should need to know, including:

• How the Positive Crankcase Ventilation system works
• The parts you’ll need to service you PCV system
• How to Remove the PCV Vacuum Harness Assembly
• How to Change the PCV Valves
• How to Re-Install the PCV Vacuum Harness Assembly