Fuel Injector: Service and Repair

NOTE: Faulty injectors can cause the following malfunctions:


- Engine runs rough
- Diesel knock
- Knocking in one or more cylinders
- Engine overheating
- Loss of power
- Excessive black smoke
- Increased fuel consumption
- Excessive blue smoke when starting from cold

Faulty injectors can be located by loosening the high pressure line union on each injector in turn, with the engine running at a fast idling speed. If the engine speed remains constant after loosening a line union, this indicates a faulty injector.

Special tools and equipment

- VAG 1331 Torque wrench 5 to 50 Nm (3.7 to 37 ft lb)







- 3035 Offset Wrench







Removing
- Remove injection lines with 3035.
- Remove securing nut, remove retainer and take out injector.
- Cover openings with a clean cloth.


NOTE: Always remove two-piece line set as a complete unit. Do not alter shape of lines.


Installing


NOTE: Always replace copper washer between cylinder head and injectors.


- Insert injector.
- Check mounting is seated correctly in cylinder head.
- Install retainer.
- Tightening torques: Injector lines = 25 Nm (18 ft lb); Bolt for retainer = 20 Nm (15 ft lb)
- Check DTC memory and, if necessary, repair any malfunctions and then erase, refer to "Diagnostic Trouble Code (DTC) Memory, Checking and Erasing" Testing and Inspection
- Read readiness code.

If the DTC memory has been erased or the engine control module was disconnected from permanent battery positive (B+), the readiness code must be generated again.