volkswagen Workshop Repair Guides

Volkswagen Workshop Service and Repair Manuals

General repair notes > < Safety precautions when working on ignition system
Releasing pressure in high-pressure area
Releasing pressure in high-pressure area
  WARNING
The injection system consists of a high-pressure section (maximum approx. 120 bar) and a low-pressure section (approx. 6 bar).
Prior to opening the high-pressure area, e.g. when removing the high-pressure pump, fuel rail, injectors, a fuel line, or the fuel pressure sender -G247-, the fuel pressure in the high-pressure area must be reduced to a residual pressure of approx. 6 bar. The appropriate procedure is described as follows.
–  Connect → Vehicle diagnostic tester and perform Guided Function „Releasing fuel high-pressure“.
–  Switch off ignition.
  WARNING
The fuel line is under pressure.
Risk of injury to eyes and skin from fuel.
Wear eye protection and protective clothing to avoid eye injuries and skin contact. Before loosening hose connections, wrap a cloth around the connection. Then release pressure by carefully opening the connection point.
–  Wrap a clean cloth around the connection and carefully open to release residual pressure of approx. 6 bar. Catch the escaping fuel.
–  After completing work, read event memory of engine control unit, erase all entries that may have been created by pulling off connector.
  Note
If the event memory was cleared, the readiness code must be generated → Vehicle diagnostic tester„Guided functions“.
   

General repair notes > < Safety precautions when working on ignition system