Audi Q7: Fuel Supply

 Refrigerant Lines in Plenum Chamber, Removing and Installing

  Caution This procedure contains mandatory replaceable parts. Refer to component overview prior to starting procedure. Mandatory Replacement Parts O-ring - Front Expansion Valve to Refrigerant Line - High Pressure Side   Caution Danger due to refrigerant coming out under pressure

 Ignition and Timing

Ignition A spark ignition (SI) engine requires a spark to initiate combustion in the combustion chamber. Voltage is supplied to the spark plug where the electricity will arc across a gap at a voltage as high as 100 kilovolts. The ECM determines the precise moment to fire each spark plug using ig