SEAT Workshop Service and Repair Manuals

Special tools, workshop equipment, testers, measuring instruments and auxiliary items required

• ◆ Fault reader V.A.G 1551 or vehicle system tester V.A.G 1552 with cable V.A.G 1551/3
• ◆ Test box V.A.G 1598/22
• ◆ 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 must be OK, checking .
• ● Fuel pump relay must be OK
• ● Fuse 14 must be OK.

Test sequence

• ‒ First check the activation of the injectors via final control diagnosis .

If one or more injectors do not click:

Checking activation

• ‒ → Pull connectors off injectors.
• ‒ Connect diode test lamp V.A.G 1527 using aux. cables from V.A.G 1594 to connector contacts of Cyl. 1.
• ‒ Introduce final control diagnosis => Page 01-61 and activate No. 1 cylinder injector.
      The LED must flash.
• ‒ Repeat check at the injector connectors for Cyls. 2...4.
• ‒ Switch off ignition.

If the LED flashes on all cylinders:

• ‒ Check resistance of injectors
  => Page 24-67

If the LED does not flash on any cylinder:

• ‒ Check voltage supply
  => Page 24-66

If the LED does not flash for one or more cylinders:

• ‒ Check wiring for open circuit between injectors (contact 1) using current flow diagram.
      Wire resistance: max. 1.5 ω

If wiring between injectors is OK:

• ‒ Check wiring to engine control unit
  => Page 24-68

Checking voltage supply

• ‒ → Connect diode test lamp to Cyl. 1 connector, contact 1 and earth.
• ‒ Introduce final control diagnosis again and activate No. 1 cylinder injector.
      The LED must light up.
• ‒ Repeat check at the injector connectors for Cyls. 2...4.
• ‒ Switch off ignition.

If the LED does not light up:

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

If the LED does not flash for one or more cylinders:

• ‒ Check wiring for open circuit between injectors (contact 1) using current flow diagram.
      Wire resistance: max. 1.5 ω

If wiring between injectors is OK:

• ‒ Check wiring (contact 2) to engine control unit => Page 24-68

Checking resistance of injectors

• ‒ → Check resistance of injectors between contacts.
      Specification: 12.0...16.0 ω

Note:

The resistance figures are valid for approx. 20 °C. At higher temperatures the resistance figures will increase.

If the specification is not attained:

• ‒ Renew defective injector

Checking wiring to engine control unit

Test conditions

• ● Activation, voltage supply and resistance must be OK.

Test sequence

• ‒ → Connect test box V.A.G 1598/22 to control unit wiring harness.

• ‒ → Check wiring between test box and connector for open circuit according to current flow diagram.
      Injector 1: Contact 2+socket 73
      Injector 2: Contact 2+socket 80
      Injector 3: Contact 2+socket 58
      Injector 4: Contact 2+socket 65
      Wire resistance: Max.1.5 ω
• ‒ Additionally check wires for short to one another.
      Specification: ∞ω

If no wiring fault is detected:

• ‒ Renew engine electronics control unit => Page 24-105.

Check injectors for leaks and quantity injected

Special tools, workshop equipment, test and measuring appliances and aux. items required

• ◆ V.A.G 1348/3 Remote control
• ◆ V.A.G 1348/3-2 Adapter
• ◆ V.A.G 1602 Calibration tester

Test conditions

• ● The fuel pressure must be in order, checking
  => Page 24-73.

Test sequence

• ‒ → Pull connectors off injectors.
• ‒ Then remove fuel rail complete.
• ‒ Pull off vacuum hose from fuel pressure regulator.
• ‒ Lift fuel rail with injectors off intake manifold and support it.

Checking for leaks

• ‒ Introduce final control diagnosis and activate injector Cyl. 1 (N30) => Page 01-61; the fuel pump must run.

Note:

This work sequence allows the fuel pump to run when the engine is not running. The idling speed switch must remain closed for this check, otherwise the selected injector will inject 5 times. Check injector for leaks (visual check).

• ‒ Check injector for leaks (visual check). Only 1 to 2 drops per minute must emit from each valve when fuel pump is running.

If the fuel loss is greater:

• ‒ Switch off ignition and renew leaking injector.

Note:

Always renew seals.

Checking injected quantity

• ‒ Insert injector to be checked in a measuring glass of tester for injected quantity V.A.G 1602.

• ‒ → Connect one contact of the injector to be tested to engine earth using auxiliary cables from V.A.G 1594.
• ‒ Connect the second injector contact with auxiliary cable to remote control V.A.G 1348/3 using adapter cable V.A.G 1348/3-2.
• ‒ Connect crocodile clip to battery (+).
• ‒ Introduce final control diagnosis and activate injector Cyl. 1 (N30) => Page 01-61; the fuel pump must run.
• ‒ Operate remote control V.A.G 1348/3 for 30 seconds.
• ‒ Repeat check on the other injectors. To do this use new measuring glasses.
• ‒ After all injectors have been activated, place the measuring glasses on a flat surface and compare the quantities injected.
      Specifications: 110...130 ml per injector

If the measured values of one or more injectors are above or below the prescribed specifications:

• ‒ Renew defective injector.

Perform installation of injectors in reverse order. When doing this note the following:

• ◆ Renew O-rings on all injectors and lightly moisten with clean engine oil.
• ◆ Insert injectors vertically and in the correct position into the fuel rail and secure with retaining clips.
• ◆ Fit fuel rail with secured injectors onto intake manifold and press in evenly.