With Manufacturer's Scan Tool

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

Special tools and equipment







- VAG1348/3A
- VAG1594A
- VAG1598/31
- VAG 1602

Test requirement:
- Fuel pressure OK. Testing and Inspection

Test sequence
- Remove fuel rail including fuel injectors from intake manifold. Fuel lines remain connected.
- Connect VAG1598/31 test box at wiring harness to ECM, do not connect ECM. Electrical Testing Using VAG1598/31 Test Box

Checking proper seal
- Bridge 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.
- Fuel Pump (FP) must run.
- Check proper seal of fuel injectors (visual inspection). 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 VAG1602 injection quantity test device.







- Connect one terminal of fuel injector to engine Ground (GND) using an adapter cable and an alligator clip from VAG1594A connector test kit.
- Connect second terminal of fuel injector to B+ using VAG1348/3A remote control, VAG1348/3-2 adapter cable and assisting cable.
- Bridge 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.
- Fuel Pump (FP) must run.
- Activate VAG1348/3A remote control for 30 seconds.
- Perform measurement on all fuel injectors.
- After all four fuel injectors have been activated, place measuring glasses on an even surface.
- Specified value for each fuel injector: 179 ± 14 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 value of all fuel injectors is outside of the specified range, check fuel pressure. Testing and Inspection

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

- Re-install fuel injectors together with fuel rail.