Injectors For Leaks And Quantity Injected, Check

Check Injectors For Leaks And Quantity Injected







Special tools and equipment
- VAG 1348/3 Remote control
- VAG 1348/3-2 Adapter
- VAG 1602 Calibration tester

Test conditions
- The fuel pressure must be in order, checking Testing and Inspection.

WARNING: Fuel system is under pressure! Before opening the system place a cloth around the connection. Then release pressure by carefully loosening the connection.

Test sequence
- Remove intake manifold upper section.
- Pull connector off all injectors.
- Remove fuel rail securing bolts.
- Pull off vacuum hose from fuel pressure regulator.
- Lift fuel rail with injectors off intake manifold and support it.

Checking for leaks
- Initiate Output Diagnostic Test Mode (DTM) and activate cylinder 1 fuel injector -N30- ; fuel pump must run. Scan Tool Testing and Procedures

NOTE: This work sequence allows the fuel pump to run when the engine is not running. The idle 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 ignition off and replace leaking injector.

NOTE: Always replace seals.

Checking injected quantity
- Insert injector to be checked in a measuring glass of tester for injected quantity VAG 1602.







- Connect one contact of the injector to be tested to engine Ground using auxiliary cables from VAG 1594.
- Connect second injector contact with auxiliary cable to remote control VAG 1348/3 using adapter cable VAG 1348/3-2.
- Connect alligator clip to battery positive (+).
- Initiate Output Diagnostic Test Mode (DTM) and activate cylinder 1 fuel injector -N30-; fuel pump must run. Scan Tool Testing and Procedures
- Operate remote control VAG 1348/3 for 30 seconds.
- Repeat check on other injectors. To do this use new measuring beakers.
- After all injectors have been activated, place measuring containers on a level surface and compare quantity injected.
Specification: 85 to 105 ml. per injector

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

Perform installation of injectors in reverse order. When doing this note the following:
- Replace 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.
- Install fuel rail with secured injectors onto intake manifold and press in evenly.