Audi Workshop Service and Repair Manuals

Removing and installing injectors (piezo injectors)

Special tools and workshop equipment required

t	Socket, 14 mm -3150- for vehicles up to 09.2005

t	Torque wrench -V.A.G 1331-

t	Ratchet -V.A.G 1331/1-

t	Puller -T10055- with adapter -T10055/1-

t	Socket -T40055- (17 mm)

t  Tool insert, AF 19 -V.A.G 1331/5- for vehicles from 09.2005 onwards Removing   Caution t  Always read instructions on → Chapter when working on injectors (piezo injectors). t  Follow these instructions before starting work and while working on the fuel system.   Note t  The following description shows the removal and installation of the injectors on cylinder bank 2 (left-side). t  Step required only for cylinder bank 1: Remove top section of air cleaner housing with air mass meter → Chapter

t  When removing the injectors for cylinders 5 and 6 the coolant expansion tank must be detached; coolant hoses remain connected. –  Remove engine cover panel → Chapter.   Caution t  Mark cylinder numbers on injector units. They must always be re-installed on the same cylinders. t  Observe rules for cleanliness when working on the injection system. t  Plug open connections with suitable sealing caps immediately.

–  Pull return line connections off injectors; to do so, press both tabs down and at the same time pull centre piece up to release connection -arrow-.   Note No dirt must be allowed to get into the disconnected return lines or the open connections on the injectors. –  Detach electrical connectors at injectors which are to be removed.

–  Loosen union nuts for high-pressure pipes at injectors -1- using socket -T40055-, 17 mm. –  Loosen union nuts for high-pressure pipes at rail element -2- using socket, 14 mm -3150- or tool insert, AF 19 -V.A.G 1331/5-.

–  Unbolt covers for injectors -arrows-. –  Pull covers upwards and turn them 1/4 turn (90°).

–  Unbolt clamping pieces for injectors -arrows-.

–  Pull out injectors using puller -T10055- with adapter -T10055/1-. –  After removal, lay injectors on a clean cloth. Important instructions for installing injectors: l  When removing and installing, always renew the following components and seals/O-rings: „copper seal“, „O-ring for injector bore“, „O-ring for injector return connection“. l  The following components and seals/O-rings must always be renewed when an injector is renewed: „clamping piece“, „copper seal“, „O-ring for injector bore“, „O-ring for injector return connection“ l  Used injectors and high-pressure pipes may only be re-installed on the same cylinders. l  Make sure that the injectors and the surrounding areas are clean before installing. l  The injectors must be completely undamaged. l  Lubricate all O-rings with engine oil or assembly oil before installing.   Note t  Note identification marks for cylinder allocation when re-installing high-pressure pipes. t  The high-pressure pipes can be re-used after performing the following checks: t  Check taper seats of high-pressure pipes for deformation and cracks. t  The bore of the pipe must not be distorted, restricted or otherwise damaged. t  Corroded pipes must not be used again. If a used injector is being re-installed: –  Spray tip of injector nozzle with rust-releasing spray. Wait approx. 5 minutes and wipe off soot particles and oil with a cloth. –  If an injector is very dirty, the tip of the nozzle should also be cleaned with a soft brass wire brush to make it easier to remove the copper seal. Do not apply the wire brush to the bores in the nozzle. –  To remove the old copper seal from the injector, clamp the seal carefully in a vice so that it is just held between the jaws without turning. Then carefully pull and twist the injector out of the copper seal by hand. –  Clean off deposits under the copper seal using a suitable scraper. –  Fit new copper seal. –  Renew O-rings -2- at all return line connections.   Note Lubricate all seals with engine oil or assembly oil before installing. –  To remove carbon deposits from the injector sealing surface, clean the injector seat in the cylinder head with a cloth soaked in engine oil or rust solvent. Take care not to damage the sealing surface. –  Install injectors.   Note t  Note identification marks for cylinder allocation when re-installing high-pressure pipes. t  The high-pressure pipes can be re-used after performing the following checks: t  Check taper seats of high-pressure pipes for deformation and cracks. t  The bore of the pipe must not be distorted, restricted or otherwise damaged. t  Corroded pipes must not be used again. t  Lubricate threads of union nuts with fuel. –  Hand-tighten union nuts on high-pressure pipes. Make sure that connections are not under tension.

–  To tighten unions of high-pressure pipes at injectors, use torque wrench -V.A.G 1331- with ratchet -V.A.G 1331/1- and socket -T40055-. Vehicles up to 09.2005:

–  To tighten unions of high-pressure pipes at rail elements, use torque wrench -V.A.G 1331- with ratchet -V.A.G 1331/1- and socket, 14 mm -3150-. Vehicles from 09.2005 onwards:

–  To tighten unions of high-pressure pipes at rail elements, use torque wrench -V.A.G 1331- with tool insert, AF 19 -V.A.G 1331/5-. All vehicles: –  Press return line connections carefully over the seals and onto the injector units (check seal for damage before connecting return line). The catch should engage audibly. Then press release pin down carefully. After replacement of one or more injectors, the „injector delivery calibration values“ and „injector voltage calibration values“ for the new injectors must be written into the engine control unit. Additionally, check that the „injector delivery calibration values“ and „injector voltage calibration values“ are correctly entered for all the other injectors. Do NOT attempt to re-enter these calibration values if the correct values are already stored in the engine control unit. Bleeding fuel system and checking for leaks   Note The fuel system is self-bleeding; do not open the high-pressure connections. –  Run engine at idling speed for several minutes and then switch off. –  Switch off ignition. –  Check the complete fuel system including all 6 return line connections for leaks. Renew the affected component if leakage still occurs after tightening to the correct torque.   Note The return lines can only be renewed together with the pressure retention valve as one unit. –  After completing the repair, road-test the vehicle over a distance of at least 20 km. Accelerate with full throttle at least once. Then inspect the high-pressure section of the fuel system again for leaks.   Note If there is any air left in the fuel system, the engine may switch to the backup mode ('emergency running' mode) during the road test. Switch off the engine and erase the fault memory. Then continue the road test. Tightening torques

Component		Nm
Injector in cylinder head		10
Cover for injector to cylinder head		5
Rail element to cylinder head		23
High-pressure pipes		25
Bracket for intake connecting pipe to cylinder head		9
Intake connecting pipe	Intake manifold	9
to:	Bracket	9
Hose clips for air intake hose (13 mm wide)		5.5