Quantity/Proper Seal/Spray Pattern Fuel Injectors Checking

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


Special Tools and Equipment







- VAG1348/3A with VAG1348/3-2
- VAG1594A
- VAG1598/31
- VAG1602
- VAS5051 with VAG5051/1
or
- VAG1551 with VAG1551/3B

Test requirement:
- Fuel pressure OK, checking. Testing and Inspection

Test sequence
- Remove fuel distributor including fuel injectors from intake manifold. Fuel lines remain connected.
- Connect VAG1598/31 test box at wiring harness to ECM, do not connect ECM. Refer to "Scan Tool Testing/Wire And Component Test Using VAG1598/31 Test Box", Testing and Inspection
- 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).


NOTE: Fuel Pump (FP) relay is supplied with B+ via the central electric (terminal 30). Fuel Pump (FP) relay receives minus via the cable bridge in test box. The Fuel Pump (FP) is now running constantly.


Checking Proper Seal
- 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 (disconnect cable bridge) 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 the 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 wires from VAG1594A adapter test kit.
- Fuel Pump (FP) must run.
- Operate VAG1348/3A 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 (disconnect cable bridge) 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. Testing and Inspection


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


- Install fuel injectors together with fuel distributor.