Audi Workshop Service and Repair Manuals

Checking for injectors sticking open (piezo injectors) If one of the injectors is sticking open, this means that the injector needle is not closing fully and fuel escapes into the cylinder.

Special tools and workshop equipment required

t	Torque wrench -V.A.G 1331-

t	Ratchet -V.A.G 1331/1-

t	Tool insert, AF 19 -V.A.G 1331/5- for vehicles from 09.2005 onwards

t	Socket -T40055- (17 mm)

t  Socket, 14 mm -3150- for vehicles up to 09.2005 t  Cap -T40162-

t  Screw plug -T40040-   WARNING t  Always read rules for cleanliness and instructions for working on fuel system → Chapter. t  Follow these instructions and rules for cleanliness before starting work and while working on the fuel system. –  Erase fault memory of engine control unit. –  Remove engine cover panel → Chapter. –  Clean all connections (with commercial cleaning solution etc.) before removing.   Note t  Make sure all parts are clean; no dirt must be allowed to enter the fuel system. t  Check all cylinders in turn. –  Dry all components after cleaning. –  Using socket, 14 mm -3150- or tool insert, AF 19 -V.A.G 1331/5-, unscrew union nut for No. 1 cylinder at rail element. Also loosen union nut on injector slightly using socket -T40055-, 17 mm. Seal off open connection on injector pipe. –  Seal off open connection on rail element using plug for rail connection -T 40040-. –  The electrical connector of the relevant injector must remain connected. –  Perform test drive.   Note t  The fault „positive control deviation“ should no longer be indicated when the defective injector has been located. t  Other fault messages may possibly be stored in the memory. These result from previous steps and can be disregarded. –  Interrogate fault memory after road-testing vehicle. If a fault relating to „positive control deviation“ is still being indicated, repeat the above steps for all rail element connections until the fault is no longer indicated after the road-test. Observe all instructions for connecting injector pipes.   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. –  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-, 17 mm. 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-. –  Check fuel system for leaks → Chapter.

Component	Nm
High-pressure pipes between rail element and injectors	25