volkswagen Workshop Repair Guides

Volkswagen Workshop Service and Repair Manuals

Checking and adjusting quantity injected by accelerator pump > < Checking and adjusting choke valve gap
34 PICT, Keihin carburettor and ignition system
Servicing Keihin carburettor 08.78 >
Checking vacuum system of pull-down unit

Vacuum reservoir leak test.

 
V22-0842
  • ‒ Remove air cleaner.
  • ‒ → Pull vacuum hose off vacuum reservoir -arrow-.
 
V22-1691
  • ‒ → Connect up vacuum tester V.A.G 1368 between vacuum reservoir and vacuum hose detached.
  • ‒ Set vacuum tester to throughflow.
  • ‒ Start engine and let it idle until a vacuum of approx. 500 mbar is indicated on vacuum tester.
  • ‒ Set vacuum tester such that vacuum is held on reservoir end.
    The vacuum may not drop off within 2 minutes. Otherwise vacuum reservoir is to be renewed.
  • ‒ Attach vacuum hose to vacuum reservoir.

Checking pull-down unit for leaks

 
V22-0844
  • ‒ → Pull vacuum hose off vacuum reservoir at T piece and seal connection -arrow-.
  • ‒ Pull vacuum hose pull-down unit.
 
V22-1692
  • ‒ → Connect up vacuum tester between vacuum hose/servo unit and pull-down unit.
  • ‒ Set vacuum tester to throughflow.
  • ‒ Start engine and let it idle until a vacuum of approx. 500 mbar is indicated on vacuum tester.
  • ‒ Set vacuum tester such that vacuum is held on pull-down end.
    The vacuum must not drop off within 2 minutes. Otherwise renew pull-down unit/vacuum hoses.

Checking and adjusting quantity injected by accelerator pump > < Checking and adjusting choke valve gap