Volkswagen Workshop Service and Repair Manuals

Checking activation

Special tools, testers and auxiliary items

• ◆ 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

• ● Engine speed sender OK.
• ● Fuel pump relay OK

Test sequence

• ‒ → Pull plug -1- off connection -2- and connect diode test lamp V.A.G 1527 with aux. cables from V.A.G 1594 to the contacts of the plug.
• ‒ Operate starter and check injector voltage supply.
       LED must flicker
• ‒ Repeat check on injectors 2...4.

The LED does not flicker:

• ‒ Switch off ignition

• ‒ → Connect test box V.A.G 1598/18 to control unit wiring loom.

• ‒ → Check wiring between test box and connector for open circuit according to current flow diagram.
       No. 1 cyl. injector: Contact 2+socket 24
       No. 2 cyl. injector: Contact 2+socket 02
       No. 3 cyl. injector: Contact 2+socket 25
       No. 4 cyl. injector: Contact 2+socket 26
       Wire resistance: Max.1.5 ω
• ‒ Check wiring between connector for injectors contact 1 and relay plate for open circuit according to current flow diagram.
       Wire resistance: Max. 1.5 ω
• ‒ Additionally check wires for short to one another.
       Specification: ∞ω

Checking resistance of injectors

• ‒ → Check resistance of injectors individually
       Specification: 15...20 ω

If the specification is not attained, replace injector(s) as necessary.

Checking spray pattern and for leaks

Special tools, testers and auxiliary items

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

Test sequence

• ‒ Remove toothed belt guard upper part.
• ‒ Remove fuel manifold complete with injectors , Item 5 .
• ‒ → Hold injectors in the measuring appliance V.A.G 1602.

• ‒ → Pull plug off coolant temperature sender (G62).
• ‒ Set digital potentiometer V.A.G 1630 -side A- to 15 kωand using aux. cables from V.A.G 1594 connect to contacts 1+3 of disconnected plug.
• ‒ Pull plug off ignition transformer.
• ‒ Operate starter (2nd person required). The injectors must pulsate and spray in accordance with firing order.
• ‒ Switch off ignition and 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.