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 1+5 of the plug.
• ‒ Operate starter.
       The LED must flash
• ‒ Repeat check on contacts 2+5, 3+5 and 4+5.

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 5 pin connector for open circuit according to current flow diagram.
       Contact 1+socket 24
       Contact 2+socket 25
       Contact 3+socket 26
       Contact 4+socket 2
       Wire resistance: Max.1.5 ω
• ‒ Check wire between 5 pin connector contact 5 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 with wiring

• ‒ Check individual injector resistance with hand multimeter V.A.G 1526 on the contacts of the connector -2-.

•      Specification: 15...20 ω

If the specification is not attained:

• ‒ Remove intake manifold upper part.

• ‒ Remove fuel manifold, dismantle and repeat check on the injectors individually, if necessary renew injector(s).

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

• ‒ → 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 disconnected plug.
• ‒ Remove intake manifold upper part.

• ‒ Pull 5 pin connector out of retainer and remove wiring from clips.
• ‒ Remove fuel distributor (fuel hoses remain connected).
• ‒ → Hold injectors in the measuring appliance V.A.G 1602.
• ‒ 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.