1.4 MPI engine (EA111) · Mixture preparation – injection · Injection system

Checking injectors

Checking spray pattern and for leaks

Special tools and workshop equipment required

  • Torque wrench (5 … 50 Nm) - V.A.G 1331-
  • Adapter set - V.A.G 1594C-
  • Digital potentiometer - V.A.G 1630-
  • Measuring glass

Prerequisites for check

  • Fuel pressure must be OK.

Test sequence

  • Pull off 2-pin connector from coolant temperature sender - G62- -arrow-.
  • 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 3 (1.5 Assembly overview - fuel rail with injectors).
  • 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 produce a pulsating 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:

Install injectors in reverse order. During this step, observe the following:

  • Renew O-rings on all injectors and lightly moisten with clean engine oil.
  • Fit fuel rail with secured injectors onto intake manifold and tighten evenly.