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Checking intake air preheating > < Cleaning throttle valve moduleJ338

Polo Mk5

Checking injectors
Checking injectors
Checking spray pattern and for leaks
   
Special tools and workshop equipment required
t  Torque wrench (5…50 Nm) -V.A.G 1331-
t  Auxiliary measuring set -V.A.G 1594C-
t  Digital potentiometer -V.A.G 1630-
t  Measuring glass

Test prerequisite
l  Fuel pressure must be OK.
Test procedure
–  Remove air filter housing (engine codes AUA, AUB, BBY, BBZ and BKY) → Chapter.
–  Remove air filter housing (engine codes BUD and CGGB) → Chapter.
   
–  Pull off 2-pin connector from coolant temperature sender -G62--arrow-.
  N24-1085
–  Connect digital potentiometer -V.A.G 1630- using adapter cables from auxiliary measuring set -V.A.G 1594C- to contacts -1- and -2- from connector and set connected side to 15 kΩ.
–  Unclip wiring harness for injectors from intake manifold and thermostat housing.
–  Remove fuel rail complete with all injectors from intake manifold (fuel hoses remain connected) → Item.
  S24-0342
–  Hold a small container under the injector to be checked and pull connectors off all other injectors.
–  Ask another person to operate the starter. Injector must issue pulsed spray.
–  Repeat check on other injectors. Make sure that only the valve being tested is connected.
–  Then check the injectors for leaks. No more than 2 drops/min must escape from each injector.
If the fuel loss is greater:
–  Switch off ignition.
–  Renew defective injector → Item.
Install injectors in reverse order. In the process, note the following:
t  Renew O-rings on all injectors and lightly moisten with clean engine oil.
t  Fit fuel rail with secured injectors onto intake manifold and tighten evenly.
  S24-0340

Checking intake air preheating > < Cleaning throttle valve moduleJ338