Volkswagen Workshop Service and Repair Manuals

Checking voltage supply

• ‒ Pull the H.T. lead from the out at the distributor and earth with aux. cables from V.A.G 1594.

• ‒ → Pull plug off warm-up -N9- and connect diode test lamp V.A.G 1527 with aux. cables from V.A.G 1594.
• ‒ Operated starter. Diode must light up, otherwise there is an open circuit and this must be located and eliminated with aid of CFD:

=> Current flow diagrams, Electrical fault finding and Fitting locations

Checking control pressure - engine cold

• ● Engine cold/ambient temperature
  Approx. 20...30 °C

• ‒ Pull plug off warm-up valve -N9- and auxiliary air valve -N21-.

• ‒ → Connect pressure gauge V.A.G 1318 between fuel meting distributor and control pressure pipe of the warn-up valve. To do this screw the pressure gauge connector into the fuel metering distributor.

• Always use new sealing rings.

• ‒ Open cut-off valve on pressure gauge (lever in flow direction -A-).
• ‒ Start engine and run it at idling speed.
• ‒ The control pressure must adjust itself to the specified figure immediately after starting.

Specifications (bar):

Checking control pressure-engine warm

• ● Open cut-off valve on pressure gauge.

• ‒ Allow engine to idle.
• ‒ Connect plugs to warm-up and aux. air valve and aux. air valve.

• Alter 1.3...2.5 minutes (engine code letters EG) or after 2.5...5.0 minutes (engine code letters DE, JH, JJ, KT) The control pressure must increase to
       3.4...3.8 bar.