Replacing injectors (Audi 100 C3)

Damage to the injectors can cause a loud knocking sound in the engine. In this case, leave the engine idling and unscrew the nuts securing the fuel lines to the injectors one by one. If the knocking stops when you unscrew the next nut, then this injector is faulty. At service stations, the injectors can be checked using a pressure gauge. The main signs of damage to the injectors are: engine misfires, knocking in one or more cylinders, engine overheating, loss of engine power, black smoke from the exhaust pipe, high fuel consumption.

Execution order

1. Flush the fuel lines with a cleaning solution and cold water.

2. Loosen the fuel line fastening nuts and remove the fuel lines. Do not bend the fuel lines or change their shape.

3. Unscrew the injectors.



4. Replace the sealing washers between the injectors and the cylinder head. Install the washers as shown in the figure (the arrow points towards the cylinder head).

5. Install new injectors and tighten to 70 Nm (7.0 kgf·m).

6. Install the fuel supply lines and tighten the mounting nuts to a torque of 25 N·m (2.5 kgf·m).

(This publication is borrowed from the resource audimanual.ru)