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

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







Recommended special tools and equipment
- VAG1348/3A remote control with VAG1348/3-2 adapter cable
- VAG1594A connector test kit
- VAG1598/31 test box
- V.A.G 1602 tester for quantity of injected fuel

Test requirements:
- Fuel pressure OK, checking.
- Ignition switched off.

Test sequence
- Remove fuel distributor including fuel injectors from intake manifold. Fuel lines remain connected.
- Connect test box to wiring harness of Engine Control Module (ECM); ECM is not connected.

Checking proper seal
- Bridge terminals 1 and 65 at test box using wires e.g. from V.A.G 1594 A adapter test kit.
- Switch ignition on.
- Fuel Pump (FP) must run.
- Check proper seal of fuel injectors (visual inspection). With Fuel Pump (FP) running, only 1 to 2 drops per minute may drip out per injector.
- If fuel loss is greater, stop Fuel Pump (FP) from running (switch ignition off) and replace faulty fuel injector.

Checking injection quantity







- Insert fuel injector to be tested in a measuring glass from e.g. V.A.G 1602 injection quantity test device.







- Connect one terminal of fuel injector to engine Ground (GND) using an adapter cable and an alligator clip e.g. from VAG1594A connector test kit.
- Connect the second terminal of fuel injector to B+ using e.g. VAG1348/3A remote control, VAG1348/3-2 adapter cable and assisting cable.
- Bridge terminals 1 and 65 at test box using wires e.g. from V.A.G 1594 A adapter test kit.
- Switch ignition on.
- Fuel Pump (FP) must run.
- Operate remote control for 30 seconds.
- After all three fuel injectors of one cylinder row have been activated, place measuring glasses on an even surface.
- Specified value for each fuel injector: 90 to 125 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.
- Repeat test at fuel injectors of second cylinder row.
- If the measured values of all fuel injectors are outside the specified range, check fuel pressure.

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

- Install fuel injectors together with fuel distributor.

Final procedures
After repair work, the following work steps must be performed in the mentioned sequence:
1. Check DTC memory
2. If necessary, erase DTC memory
3. If DTC memory was erased, generate readiness code

- End diagnosis and switch ignition off.