Fuel Injectors, Checking - II

Check Fuel Injectors

Checking Injection Quantity And Proper Seal Of Fuel Injectors







Special tools, testers and auxiliary items required
- Remote Control Connection V.A.G 1348/3
- Adapter V.A.G 1348/3-2
- Injector Rate Tester V.A.G 1602
- Connector Test Set V.A.G 1594 A
- Adapter Cable V.A.G 1598/31

Test conditions
- Fuel pressure must be OK, checking. Fuel Pressure Regulator and Residual Pressure, Checking

Test sequence







- Connect Adapter Cable V.A.G 1598/31 to control module wiring harness. The engine control module remains disconnected.







- Disconnect Fuel Injector connectors.
- Remove fuel rail securing bolts.
- Disconnect vacuum hose from fuel pressure regulator.
- Lift fuel rail with injectors off intake manifold and support it.
- Bridge test box sockets 1 and 65 using Adapter Cables from Connector Test Kit V.A.G 1594 A.

NOTE: This work step allows the fuel pump to run when the engine is not running.

- Switch ignition on.

Checking for leaks
- Check injectors for leaks (visual inspection). Only 1 to 2 drops per minute may emit from each valve when fuel pump is running.

If the fuel loss is greater:
- Switch off ignition and replace leaking Fuel Injector.

NOTE: Always use new seals.

Injection quantity, checking

Test conditions
- Adapter Cable V.A.G 1598/31 still connected and test box sockets 1 and 65 bridged with Adapter Cables from Connector Test Kit V.A.G 1594 A.

Test sequence
- Place a Fuel Injector to be tested into a graduated measuring glass of Injection Rate Tester V.A.G 1602.







- Connect one terminal of Fuel Injector to be checked to engine Ground (GND) using Adapter Cables from Connector Test Kit V.A.G 1594 A.
- Connect second Fuel Injector terminal with Adapter Cable to Remote Control Connection V.A.G 1348/3 using Adapter Cable V.A.G 1348/3-2.
- Connect alligator clip to battery (+).
- Operate Remote Control Connection V.A.G 1348/3 for 30 seconds.
- Repeat check on the other injectors. Use new graduated measuring glasses for this.
- After all Fuel Injectors have been activated, place graduated measuring glasses on a level surface and compare quantity of injected fuel.
- Specification: 133 to 157 ml per injector

If the measured value of one or more Fuel Injectors is below or above the indicated specified value:
- Replace the defective Fuel Injector.

Perform installation of injectors in reverse order. When doing this note the following:
- Replace O-rings on all injectors and lightly moisten with clean engine oil.
- Insert Fuel Injectors into fuel rail perpendicular and in correct position, and secure them with retaining clips.
- Position fuel rail with secured Fuel Injectors on intake manifold and apply uniform pressure to press it in.
- Check DTC memory of Engine Control Module (ECM), repair any stored malfunctions and then erase DTC memory. Reading Diagnostic Trouble Codes