volkswagen Workshop Repair Guides

Volkswagen Workshop Service and Repair Manuals

Exhaust system > < Removing and installing parts of the activated charcoal filter system
4-Cyl. injection engine (4-valve), Mechanics
Removing and installing parts of fuel supply system
Checking fuel tank breather

Special tools, testers and auxiliary items

  • ◆ Hand vacuum pump V.A.G 1390
  • ◆ Vacuum tester V.A.G 1368

Test conditions

  • ● Ignition must be switched off
 
N20-0028

Test sequence

  • ‒ Remove air cleaner

=> Digifant injection and ignition system (4-valve); Repair group 24; Digifant injection and ignition system; Servicing injection part

  • ‒ → Pull breather hose -1- off at solenoid valve -2-.
  • ‒ Connect hand vacuum pump V.A.G 1390 to hose -1-.
  • ‒ Pull breather hose -3- from fuel tank off activated charcoal filter -4- and connect to -connection A- of vacuum tester V.A.G 1368.
  • ‒ Connect vacuum tester V.A.G 1368 -connection B- to activated charcoal filter.
  • ‒ Set vacuum tester to position -B-.
  • ‒ Operate hand vacuum pump V.A.G 1390 several times.
         Vacuum must not
    build-up.

If vacuum builds-up:

  • ‒ Check breather connection -5- on activated charcoal filter -4- for soiling, clean if necessary.

If vacuum does not build-up:

  • ‒ Remove fuel filler cap from filler neck.
 
N20-0029
  • ‒ → Connect hand vacuum pump V.A.G 1390 to vacuum tester V.A.G 1368 -connection B-.
  • ‒ Set vacuum tester to -A/B- position.
  • ‒ Operate V.A.G 1390 several times. Vacuum must
         not build-up.

If vacuum builds-up:

  • ‒ Check gravity valve , Item 5
  • ‒ Check line -1- from fuel tank for blockage.

If vacuum does not build-up:

  • ‒ Refit fuel filler cap.
  • ‒ Operate hand vacuum pump V.A.G 1390 several times.
         Vacuum must not
    build-up.

Note:

If the fuel level in the tank is low the hand vacuum must be operated at least 20...30 times.

If vacuum builds-up:

  • ‒ Replace fuel tank cap.

Exhaust system > < Removing and installing parts of the activated charcoal filter system