Audi Workshop Service and Repair Manuals

Special tools,
testers and equipment required

• ◆ V.A.G 1348/3-2
• ◆ V.A.G 1348/3A
• ◆ V.A.G 1594 A
• ◆ V.A.G 1602
• ◆ VAS 5051 with VAS 5051/1

• or

• ◆ V.A.G 1551 with V.A.G 1551/3 A

Test requirements:

• ● Fuel pressure OK, checking .

Work sequence

• ‒ Remove the intake hose between air mass meter and air cleaner.
• ‒ Unplug connectors from injectors.

• ‒ → Unscrew fuel manifold from intake manifold.
• ‒ Pull vacuum hose off fuel pressure regulator.
• ‒ Lift fuel manifold, together with injectors, off intake manifold and support it.

Leak test

• ‒ Start final control diagnosis and actuate fuel pump relay -J17.
• ‒ The fuel pump should run.

Note:

This step is merely designed to make the fuel pump run with the engine stopped.

• ‒ Check injectors for leaks (visual check). When the fuel pump is running, only 1 or 2 drops a minute should escape from each injector.

• ‒ If the fuel loss is greater than this, switch off the fuel pump (terminate final control diagnosis) and replace the faulty injector.

Note:

Renew O ring.

Check injection quantity

• ‒ → Place the injector which is to checked into the measuring glass of injection quantity tester V.A.G 1602.

• ‒ → Connect one of the injector contacts to the engine earth using a test cable and crocodile clip from the V.A.G 1594 A.
• ‒ Connect second contact of injector with remote control V.A.G 1348/3A, adapter lead V.A.G 1348/3-2 and auxiliary cable to positive.

• ‒ Activate remote control V.A.G 1348/3A for 30 seconds.
• ‒ Once all three injectors of a cylinder bank have been actuated, place the three measuring glasses on a flat surface.
• ‒ Specified value per injector: 85 ... 100 ml
• ‒ If the measured value for one or more of the injectors is outside the tolerance range, renew the defective injector(s).
• ‒ Repat the check on injectors of second cylinder bank.
• ‒ If the measured values for all the injectors are outside the tolerance range, check the fuel pressure => Page 24-27.

Note:

When checking the injection quantity, also check the spray pattern. The spray pattern should be the same for all the injectors.

Installation of the fuel manifold together with injectors is performed in the reverse sequence. The following points should be noted when installing:

• ● Renew the O-rings at all opened connections. (When renewing the front O-ring, make sure not to remove the plastic cap from the injector head. The O-ring must be pulled off over the plastic cap.)
• ● Moisten the O-rings with clean engine oil.
• ● Insert injectors perpendicularly and in correct position into fuel manifold and secure with fasteners.
• ● Place fuel manifold with secured injectors in position at intake manifold and press in evenly.