Injection Quantity, Proper Seal and Spray Pattern of Fuel Injectors, Checking

Injection Quantity, Proper Seal And Spray Pattern Of Fuel Injectors, Checking







Special tools and workshop equipment required
- V.A.G 1348/3A Remote control
- V.A.G 1594 A Connector test kit
- V.A.G 1598/31 Test box
- V.A.G 1602 Injection quantity tester
- VAS 5051 Vehicle diagnostic, testing and information system
- VAS 5051/1 Adapter

Requirements
- Fuel pressure OK, checking.

Work sequence
- Remove fuel rail including injectors installed from intake manifold. Fuel hoses remain connected.
- Connect VAG1598/31 test box at wiring harness to ECM, do not connect to ECM.

Leak test
- Jumper terminals 1 and 65 at test box using adapter cables from VAG1594A connector test kit (this step supplies Ground (GND) to one side of relay coil for Fuel Pump (FP) relay).
- Switch ignition on.

NOTE: After switching ignition on, Fuel Pump (FP) will run continuously, even with engine not running. This is true because: Fuel Pump (FP) relay is supplied with B+ via central electrics after ignition is switched on. Fuel Pump (FP) relay receives ground (GND) via the jumper in test box.

- Fuel pump must run.
- Check proper seal of fuel injectors visually. With Fuel Pump (FP) running, only 1-2 drops per minute may drip out per injector.
- If fuel loss is greater, stop Fuel Pump (FP) from running (switch off ignition) and replace faulty fuel injector.

Checking injection quantity
- Insert fuel injector to be tested in a measuring glass from VAG 1602 injection quantity test device.







- Connect one terminal of fuel injector to engine Ground (GND) using an adapter cable and an alligator clip from VAG 1594 A connector test kit.
- Connect second terminal of fuel injector to B+ using VAG 1348/3A remote control, VAG 1348/3-2 adapter cable and assisting cable.
- Jumper terminals 1 and 65 at test box with leads from adapter set VAG 1594 A.
- Switch ignition on.
- Fuel pump must run.
- Activate VAG 1348/3A remote control for 30 seconds.
- Perform measurements on all fuel injectors.
- After all four fuel injectors have been activated, place measuring glasses on an even surface.
- Specification per injector: 135 ± 10 ml.
- If measured value of one or more fuel injectors is outside of specified range, switch Fuel Pump (FP) off (switch ignition off) and replace faulty fuel injector.
- If measured values for all fuel injectors are outside specified range, check fuel pressure.

NOTE: Also check spray pattern when checking injection quantity. Spray pattern must be the same for all injectors.

- Reinstall fuel injectors together with fuel rail.