With Manufacturer's Scan Tool
Fuel Injectors, Checking For Leaks and Quantity Injected
Special tools, workshop equipment, testers, measuring instruments and auxiliary items required
- VAG 1348/3 Remote control
- VAG 1348/3-2 Adapter
- VAG 1594 A Adapter set
- VAG 1598/31 Test box
- VAG 1602 Calibration tester
Test prerequisites
- The fuel pressure must be in order, checking. Refer to "Fuel Pressure Regulator/Testing and Inspection".
Testing and Inspection
Test sequence
- Remove intake manifold:
- Then remove fuel rail complete (fuel lines remain connected).
Checking for leaks
- Initiate Output Diagnosis Test Mode (DTM).
The fuel pump must run.
NOTE: This work sequence allows the fuel pump to run when the engine is not running.
- Check fuel injector for leaks (visual check). Only 1 to 2 drops per minute must emit from each fuel injector when fuel pump is running.
- Switch off ignition.
If the fuel loss is greater:
- Replace faulty fuel injector, item 7.
Observe the following when installing fuel injectors:
- Replace O-rings on all fuel injectors and moisten then lightly with clean engine oil.
- Insert fuel injectors vertically and in the correct position into the fuel rail and secure with retaining clips.
- Set fuel rail with secured fuel injectors on cylinder head and press in evenly.
- The connectors must audibly engage in the fuel injectors when pushed on.
- Check DTC memory, repair malfunctions if necessary and then erase DTC memory. Refer to "Displaying and Reading Trouble Codes/With Manufacturer Scan Tool/DTC Memory Checking and Erasing",
Testing and Inspection
- Erase learned values and adapt Motronic Engine Control Module (ECM) -J220- again. Refer to "Computers and Control Systems/Engine Control Module".
- Read readiness code. If the DTC memory has been erased or the Motronic Engine Control Module (ECM) -J220- was disconnected from battery positive (B+), the readiness code must be generated again. Refer to "Monitors, Trips and/or Drive Cycle (Readiness Codes)/Reading Readiness Code".
Testing and Inspection
Refer to "Monitors, Trips and/or Drive Cycle (Readiness Codes)/Generating Readiness Code".
Testing and Inspection
Checking quantity injected
- Remove wiper arms and cowl panel:
- Connect VAG 1598/31 test box to control module wiring harness. The Motronic Engine Control Module (ECM) -J220- remains disconnected.
- Switch on ignition.
- Jumper test box sockets 2 and 65 using adapter cables from VAG 1594. The fuel pump must run.
NOTE This work sequence allows the fuel pump to run when the engine is not running.
- Insert fuel injector to be checked in a measuring glass of calibration tester VAG 1602.
- Connect one terminal of the fuel injector to be tested to engine ground (GND) using adapter cables from VAG 1594.
- Using adapter cables connect the second fuel injector terminal to remote control VAG 1348/3 with adapter cable VAG 1348/3-2.
- Connect crocodile clip to battery (+).
- Operate remote control VAG 1348/3 for 30 seconds.
- Repeat check on the other fuel injectors. Use another (clean and dry) measuring beaker for this.
- After all fuel injectors have been activated, place the measuring glasses on a horizontal surface and compare the quantity injected.
Specification: 110 to 130 ml per fuel injector
- Switch off ignition.
If the measured values of one or more fuel injectors are above or below the prescribed specifications:
- Replace faulty fuel injector, item 7.
Observe the following when installing fuel injectors:
- Replace O-rings on all fuel injectors and moisten then lightly with clean engine oil.
- Insert fuel injectors vertically and in the correct position into the fuel rail and secure with retaining clips.
- Set fuel rail with secured fuel injectors on cylinder head and press in evenly.
- The connectors must audibly engage in the fuel injectors when pushed on.
- Check DTC memory, repair malfunctions if necessary and then erase DTC memory. Refer to "Displaying and Reading Trouble Codes/With Manufacturer Scan Tool/DTC Memory Checking and Erasing".
Testing and Inspection
- Erase learned values and adapt Motronic Engine Control Module (ECM) -J220- again. Refer to "Computers and Control Systems/Engine Control Module".
- Read readiness code. If the DTC memory has been erased or the Motronic Engine Control Module (ECM) -J220- was disconnected from battery positive (B+), the readiness code must be generated again. Refer to "Monitors, Trips and/or Drive Cycle (Readiness Codes)/Reading Readiness Code".
Testing and Inspection.
Refer to "Monitors, Trips and/or Drive Cycle (Readiness Codes)/Generating Readiness Code".
Testing and Inspection