Injectors, Checking For Leaks and Quantity Injected

Injectors, Checking For Leaks And Quantity Injected

Engine Codes AVH, AZG, BEV, BGD)







Special tools, testers and auxiliary items required
- Remote control V.A.G1348/3
- Adapter V.A.G1348/3-2
- Injection rate tester V.A.G1602
- Adapter set V.A.G1594A
- Test box V.A.G1598/31

Requirements
- Fuel pressure must be OK, checking. Checking Fuel Pressure Regulator and Holding Pressure

Work sequence
- Remove plenum chamber inner cover on left side.







- Connect test box V.A.G1598/31 to control module wiring harness. Engine control module remains disconnected.
- Remove intake manifold upper part.
- Disconnect connectors from all injectors.
- Remove fuel rail securing bolts.


Engine codes AVH, AZG, BDC
- Pull off vacuum hose from fuel pressure regulator.

Continued for all engine codes
- Pull hose off air pipe for air shrouded injectors if part of equipment.
- Lift fuel rail along with injectors off intake manifold lower part and support (fuel lines remain connected).
- Bridge test box sockets 1 and 65 using adapter cables from adapter set V.A.G1594 A.

NOTE: This step serves only to have the fuel pump running when the engine is stopped.

Checking for leaks
- Switch ignition on.
- Check injectors for leaks (visual check). Only 1 to 2 drops per minute may emit from each valve when fuel pump is running.

If the fuel loss is greater:
- Switch off ignition.
- Replace faulty injector.

Checking quantity injected

Requirements
- Test box V.A.G1598/31 still connected and test box sockets 1 and 65 bridged with adapter cable from adapter set V.A.G1594 A.

Work sequence
- Insert injector to be checked into measuring beaker of injection rate tester V.A.G1602.







- Connect one contact of injector to be tested to engine Ground using auxiliary cables from V.A.G1594 A.
- Connect second contact of injector to remote control V.A.G1348/3 with adapter cable V.A.G1348/3-2.
- Connect alligator clip to battery positive (+).
- Switch on ignition. Fuel pump must run.

NOTE: In the following injection quantity test, the spray pattern must also be checked. The spray pattern must be the same for all injectors.

- Operate remote control V.A.G1348/3 for 30 seconds.
- Repeat check on other injectors. Use new measuring beakers.
- After all injectors have been activated, place measuring beakers on a horizontal surface and compare injected quantity.
- Specification: 85 to 105 ml per injector

If the measured values of one or more injectors are above or below the prescribed specifications:
- Switch off ignition.
- Replace faulty injector.

Observe the following when installing injectors:
- Replace O-rings on all injectors and lightly moisten them 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.
- Read Diagnostic Trouble Code (DTC) memory of engine control module. If necessary, correct faults and erase DTC memory. Reading and Clearing Diagnostic Trouble Codes