Volkswagen Workshop Service and Repair Manuals

Checking activation

Special tools, testers, measuring instruments and auxiliary items required

• ◆ Test box V.A.G 1598/18
• ◆ Hand multimeter V.A.G 1526 or multimeter V.A.G 1715
• ◆ Diode test lamp V.A.G 1527
• ◆ Adapter set V.A.G 1594
• ◆ Current flow diagram

Check conditions

• ● Hall sender in distributor must be OK.
• ● Fuel pump relay must be OK

Test sequence

• ‒ Remove air cleaner , Fig. 2 .

• ‒ → Pull connector off injectors -arrows-.
• ‒ Connect diode test lamp V.A.G 1527 using aux. cables from V.A.G 1594 to connector contacts of Cyl. 1.
• ‒ Operate starter.
       The LED must flicker
• ‒ Repeat check at the injector connectors Cyl. 2...4.

The LED does not flicker on any cylinder:

• ‒ → Connect diode test lamp to connector Cyl. 1, contact 1 and earth.
• ‒ Operate starter.
       The LED must light up

If the LED does not light up:

• ‒ Check wire between 2 pin connector contact 1 and fuel pump relay (J17) for open circuit according to current flow diagram.
       Wire resistance: max. 1.5 ω

The LED flickers on one or several cylinders:

• ‒ → Connect test box V.A.G 1598/18 to control unit wiring loom.
• ‒ Check wiring between test box and connectors of injectors for open circuit according to current flow diagram.
       Cyl. 1 connector, contact 2+socket 7
       Cyl. 2 connector, contact 2+socket 6
       Cyl. 3 connector, contact 2+socket 28
       Cyl. 4 connector, contact 2+socket 4
       Wire resistance: Max. 1.5 ω
• ‒ Additionally check wires for short to one another.
       Specification: ∞ω
• ‒ Check wiring between connector contacts 1 of injectors for open circuit.
       Wire resistance: Max. 1.5 ω

• ‒ Additionally check wires for short to one another.
       Specification: ∞ω

Checking resistance of injectors with wiring

• ‒ → Check of resistance injectors between contacts.
       Specification: 14...17 ω

Checking spray pattern and for leaks

Special tools, testers, measuring instruments and auxiliary items required

• ◆ Adapter set V.A.G 1594
• ◆ Digital potentiometer V.A.G 1630
• ◆ Measuring unit V.A.G 1602

Test sequence

• ‒ Pull 3 pin connector off ignition transformer.

• ‒ → Pull 4 pin connector -1- off coolant temperature sender (G62) -2-.
• ‒ Connect digital potentiometer V.A.G 1630 using aux. cables from V.A.G 1594 to connector contacts 1+3 and set connected side to 15 kω.
• ‒ Pull connector off throttle valve control part, oil pressure switch and intake manifold pressure sender, and unclip wiring at intake pipe and coolant regulator housing.
• ‒ Remove fuel manifold complete with all injectors from intake pipe (fuel hoses remain connected).

• ‒ → Hold a small container under the injector to be checked and pull connectors off all other injectors.
• ‒ Operate starter, using a 2nd person. Injector must spray pulsatingly.
• ‒ Repeat check with other injectors ensuring that injector to be checked is only connected.
• ‒ Switch off ignition and afterwards check injectors for leaks. No more than
       2 drops/min
  may leak from each injector.

Note:

When installing the injectors ensure that the O rings

are not damaged.