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Checking injectors for leaks and quantity injected > < Checking components

Golf Mk5

Checking vacuum unit for intake manifold flaps
Checking vacuum unit for intake manifold flaps
  Note
Perform this test only if torque is insufficient, i.e. if elasticity or pulling power is inadequate.
Special tools and workshop equipment required
   
t  Hand vacuum pump -VAS 6213- or hand vacuum pump with accessories -V.A.G 1390-
Prerequisite
l  The variable intake manifold changeover valve -N156- has been tested with the vehicle diagnosis, testing and information system -VAS 5051- in „guided fault finding“.
Test procedure
If the variable intake manifold changeover valve -N156- is OK:
–  Start engine and run at idling speed.
  W00-10259
–  Have second person abruptly increase engine speed (throttle burst). Observe vacuum unit for intake manifold change-over:
l  The actuator must switch.
If changeover does not function as indicated:
–  Check vacuum system for leaks including vacuum reservoir on intake manifold.
–  Check mechanical change-over components for ease of movement. To do this, operate rods by hand.
–  Check vacuum lines to make sure they are connected properly.
–  Check vacuum hoses for porosity.
If no fault is found:
–  Remove air filter → Chapter.
–  Pull vacuum hose off vacuum actuator.
  N24-10233
–  Connect hand vacuum pump -VAS 6213- to vacuum actuator.
  N24-10234
–  Move slide ring -1- on hand vacuum pump -VAS 6213- to position -A- for „vacuum“.
–  Operate hand vacuum pump repeatedly.
l  The operating rod must move.
–  Pull hand vacuum pump off vacuum actuator.
l  The operating rod must move back to its original position.
If the operating rod does not move as described:
–  Renew vacuum unit.
  N24-10282

Checking injectors for leaks and quantity injected > < Checking components