Fuel Injector
Fuel Injector
Special tools, testers and auxiliary items required
• Puller (T10055) with adapter (T10055/1)
• Guide Sleeve (T10377)
• Socket (T40055)
• Torque Wrench (5-50 Nm) (V.A.G 1331)
• Ratchet, Reversible (V.A.G 1331/1)
• Follow the safety precautions when working on the diesel direct injection system. Refer to => [ Safety Precautions ] Diesel Fuel Injection.
• Observe the rules for cleanliness. Refer to => [ Clean Working Conditions ] Diesel Fuel Injection.
Always follow these instructions before and during work.
Removing
- Remove the engine cover. Refer to => [ Engine Cover ] Engine Cover.
- Remove the protective strip - item 1 - in => [ Fuel Rail and Injectors Overview ] Service and Repair, if equipped.
- Disconnect the connector - 1 - from the fuel injector to be removed.
- Before removing, dry the return line connection on the fuel injectors that will be removed (for example using a commercially available detergent).
- Dry the return line connections.
- Cover the return line connection with a cloth.
- Remove the fuel return line connection from the fuel injector that is going to be removed. Pull them upward to release them - arrow -.
• Maintain clean working conditions. Dirt and contaminants must not enter the return lines and the connections on the fuel injectors.
- Remove the high pressure line between the fuel rail and fuel injectors that will be removed.
- Remove the bolts for the sealing cap on the fuel injector that will be removed.
- Raise the sealing cap slightly and rotate it 90° to free up the fuel injector nuts.
When removing the fuel injector nuts, the nut could fall into the cylinder head. Work very carefully to avoid unnecessary work or damage.
- Remove the nuts on the corresponding fuel injector.
- Position the puller (T10055) with the adapter (T10055/1) as illustrated and remove the fuel injector upward by tapping.
Installing
Important information on installing the fuel injectors:
• The following components, seals and O-rings must be replaced each time a fuel injector is removed, and installed: "tensioning bracket", "copper washer", "O-ring for the fuel injector shaft" and the "O-ring for the fuel injector return".
• Replace the following components, seals and/or O-rings each time an injector is replaced: "tensioning bracket" "injection line" "copper washer" "injector shaft O-ring" and "injector return O-ring".
• Fuel injector must be installed in the same cylinder.
• Check the fuel injectors and installation locations for contamination before assembling.
• The fuel injectors must not have any damage.
• Lubricate all of the O-rings with assembly oil or engine oil before installing.
If a used fuel injector is installed:
- Spray the tip of the fuel injector with a rust removing spray. Remove the rust or oil particles with a cloth after approximately 5 minutes.
- To remove the used copper washer from the fuel injector, clamp the washer carefully in a vise until the clamping jaws on the vise prevent the washer from turning. Pull the fuel injector out of the copper washer by hand with a slight twisting and pulling motion.
- Use a plastic socket to install the copper washer.
- To avoid damaging the O-ring, slide the new O-ring - 2 - for the fuel return line connection over the assembly drift - 1 -.
- To remove rust particles on the fuel injector sealing surface, clean the fuel injector hole in the cylinder head with a cloth dampened with engine oil or rust remover. Do not damage the sealing flanges.
- Replace the fuel injector shaft seal using the guide sleeve (T10377).
- Slide the sealing cap on.
- Slide the tensioning bracket onto the fuel injector and make sure it is positioned correctly. Refer to => [ Tensioning Plate Installed Position ] Service and Repair.
- Insert the fuel injector in the fuel injector shaft.
When installing the fuel injector nuts, the nut could fall into the cylinder head. Work very carefully to avoid unnecessary work or damage.
- Mount the nuts on the tensioning bracket by hand and tighten them. Tightening specification, refer to - item 7 - in => [ Fuel Rail and Injectors Overview ] Service and Repair.
- Turn the sealing cap for the fuel injectors to its installed position and tighten it. Tightening specification, refer to - item 19 - in => [ Fuel Rail and Injectors Overview ] Service and Repair.
- Install the high pressure lines. Refer to => [ High Pressure Line, Installing ] Service and Repair.
• The "injector quantity calibration" and the "injection pressure calibration" for the new injectors must be must be programmed into the Engine Control Module (ECM) after replacing one or more injectors. Refer to "Guided Functions" in the vehicle diagnostic tester.