Fuel Injector
Fuel injectors, checking
Checking injectors for leaks and quantity injected
Special tools and equipment
^ V.A.G 1348/3A Remote control with V.A.G 1348/3-3 Adapter cable
^ V.A.G 1348/3-2 Adapter
^ V.A.G 1602 Calibration tester
Checking conditions
^ Check that the fuel pressure is OK.
Work sequence
- Remove fuel rail complete (fuel lines remain connected).
Checking for leaks
WARNING! Fuel system is under pressure! Before opening the system place a cloth around the connection. Then release pressure by carefully loosening the connection.
- Remove cover over fuse holder.
- Pull fuel pump relays -1- and -2- out of their sockets.
- Connect remote control VAG 1348/3 with adapter cable VAG 1348/3-3 (arrow) to fuel pump relay connection for right fuel delivery unit.
- Connect second connection of adapter cable VAG 1348/3-3 (arrow) to fuel pump relay connector for left fuel delivery unit.
- Connect alligator clip of remote control VAG 1348/3 to positive pole -1-
- Operate remote control.
If fuel pump runs:
- Check injector for leaks (visual check).
Only 1 to 2 drops per minute must escape from each valve when fuel pump is running.
If the fuel loss is greater:
- Replace faulty injector.
Pay attention to the following when installing the injectors:
^ 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 injectors installed and secured onto intake manifold lower part and press in evenly.
Checking injected quantity
Checking conditions
^ Fuel pump relays and fuses 13 and 14 are in their sockets.
- Connect test box V.A.G 1598/31 and bridge text box sockets 1 and 65 using adapter leads from adapter set V.A.G 1594.
- Insert injector to be checked in a measuring glass of tester V.A.G 1602.
- Connect one contact of injector to be tested to engine Ground using auxiliary cables from V.A.G 1594.
- Connect second injector contact with auxiliary cable to remote control V.A.G 1348/3 using adapter cable V.A.G 1348/3-2.
- Connect alligator clip to battery positive (+) terminal -1- in engine compartment.
- Switch on ignition.
- Operate remote control V.A.G 1348/3 for 30 seconds.
- Repeat check on other injectors. Use another measuring beaker for each injector.
- Switch off ignition.
- After all injectors have been activated, place measuring beakers on a horizontal surface and compare injected quantity.
Specification: 98 to 115 ml per injector
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. Note the following:
^ Replace O-rings on all injectors and 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 onto intake manifold with injectors secured and press in evenly.