Table of contents: Installation of used injectors ↓ Remove air from the fuel system and… ↓
Installation of used injectors
When installing a previously removed injector, the following must be replaced: Pressure plate Copper sealing ring Injector socket sealing ring Return fuel hose nipple sealing ring Apply corrosion remover to injector tip (from an aerosol can). After about five minutes, remove any soot and oil particles with a rag. If the nozzle is heavily contaminated, in order to make it easier to remove the copper seal, additionally clean the nozzle tip with a soft copper brush (avoid contact of the copper brush with the nozzle holes). To remove the old copper injector sealing ring, carefully clamp it in a vice so that the ring is fixed in the vice, and the injector itself can be rotated between the jaws of the vice. Using light rotational and translational movements of the hand, remove the injector from the copper sealing ring. Use a scraper to clean off any deposits accumulated under the copper sealing ring. To remove soot particles from the seating surface, clean the injector seat in the cylinder head with a cloth soaked in oil or rust remover. Replace the injector well sealing ring using the T10377 mandrel. To avoid damaging the new sealing ring, carefully slide the oiled ring onto the fuel return line nipple. Install the injectors. Tighten the union nuts of the injector fuel lines by hand. Check the installation for internal stress.
To tighten the high-pressure pipes, use a torque wrench with a ratchet and a T40055 socket. Carefully place the return pipe fittings on the injector sealing rings (check first whether the sealing rings are damaged). The nipple should lock into place with a clearly audible click. After this, you need to carefully press the clamps down.
When replacing 1 or more injectors, the "quantity correction value (IMA)" and "voltage correction value (ISA)" for the new injectors must be entered into the engine control unit. In addition, it must be checked that the "quantity correction value (IMA)" and "voltage correction value (ISA)" are entered correctly for all other injectors. If the correct correction values are entered into the engine control unit, they must not be re-entered.
Remove air from the fuel system and check it for leaks
To remove air, do not disconnect the high-pressure fuel line connectors; air will come out of the fuel system on its own. Let the engine idle for a few minutes. Then turn off the engine. Turn off the ignition. Check the entire power supply system and connections of the return fuel lines (4 pcs.) for leaks. If there is a leak, (despite tightening to the proper torque) replace the corresponding part. The return lines can only be replaced together with the pressure reducing valve. Then perform a test drive with at least one acceleration under full load, and check the high-pressure circuit of the fuel system for leaks again. If there is air left in the fuel system, the engine may go into emergency operation mode during the test drive. Switch off the engine and clear the errors from the event recorder. Then continue the test drive.
(Information obtained from this resource: AUDImanual.ru)