Injection Quantity, Seal and Spray Pattern of Fuel Injectors

Injection Quantity, Leak Tightness And Spray Pattern Of Injectors, Checking

Special tools and equipment







- Remote control V.A.G 1348/3 A with adapter cable V.A.G 1348/3-2
- Adapter set V.A.G 1594 A
- Injection rate tester V.A.G 1602
- est box V.A.G 1598/31

Requirements
- Fuel pressure OK.

Work sequence
- Remove intake manifold.
- Remove fuel rail together with injectors.Fuel hoses remain connected.

Checking for leaks







- Open cover of fuse carrier and remove fuse 28 for Fuel pump -G6- (pre-supply pump).
- Connect remote control V.A.G 1348/3 A with adapter cable V.A.G 1348/3-2 to contact 28a for fuel pump and to positive (+) battery terminal.
- Connect battery cable Ground cable.
- Activate remote control V.A.G 1348/3 A. Fuel pump must run.
- Visually check fuel injectors for leaks.
When fuel pump is running, no more than 1 to 2 drops per minute should escape from any one injector.


If fuel loss is greater:
- Replace faulty injector.

Checking injection quantity
- Connect test box V.A.G 1598/31 to wiring harness for engine control module. Engine control module is not connected. Scan Tool Testing
- Use leads from adapter set V.A.G 1594 A to bridge contacts 1 and 65 at test box.







- Disconnect electrical connectors for fuel injectors by pressing retaining tab in direction of arrow.
- Place a fuel injector in measuring glass of injection rate tester V.A.G 1602.







- Connect one contact of fuel injector to engine Ground using test lead and alligator clamp from adapter set V.A.G 1594 A.
- Connect second contact of fuel injector to remote control V.A.G 1348/3 A with adapter cable V.A.G 1348/3-2.
- Connect alligator clamp to positive (+) battery terminal.
- Use leads from adapter set V.A.G 1594 A to bridge contacts 1 and 65 at test box.
- If necessary, connect battery Ground cable.
- Switch ignition on.
Fuel pump should run
- Activate remote control VAG1348/3 A for 30 seconds.
- Perform test for all injectors using a new glass each time.

NOTE: When checking the injection quantity, also check the spray pattern. The spray pattern should be the same for all the injectors.

- Once all 6 injectors have been actuated, place measuring glasses on a level surface.
- Specification: 128 to 140 ml for each injector

If measured values for one or more injectors are outside specification:
- Stop fuel pump (switch off ignition) and replace faulty injector.

If measured values for all the injectors are outside specification :
- Check fuel pressure.
- Install injectors with fuel rail