Testing injection quantity, absence of leaks and spray pattern of injectors — AUDI

AMM AMX ASM BDV
Special tools and workshop equipment required

V.A.G 1348/3A with 1348/3-2
V.A.G 1594 A
V.A.G 1598/31
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 =>Page
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.

Test sequence

Remove fuel manifold with injectors fitted from intake manifold => Page
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. Fuel hoses remain connected.
Connect test box V.A.G 1598/31 to wiring harness for engine control unit; do not connect the engine control unit => Page
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.
Bridge contacts 1 and 65 on the test box using test leads from adapter set V.A.G 1594 A (this creates an earth connection to one side of the fuel pump relay coil).

Note:

The fuel pump relay obtains positive supply (terminal 30) directly via central electrical system. The negative voltage supply for the fuel pump relay comes via the cable bridge in the test box. The fuel pump now runs constantly.

Leak test

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 switch off fuel pump (remove cable bridge) and replace defective injector => Page
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;

Checking injection quantity

Place injector to be tested in a measuring glass from 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 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.
Jumper contacts 1 and 65 at test box with leads from adapter set V.A.G 1594A.
The fuel pump should run.

Activate the V.A.G 1348/3 A remote control for 30 seconds.
Once all three injectors of a cylinder bank have been actuated, place the three measuring glasses on a flat surface.
Specification per injector: 90...125 ml

If measured values for one or more injectors are outside tolerance, switch off fuel pump (pull off cable bridge) and replace defective injector => Page
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;
Repeat 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
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.

Note:

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

Install injectors with fuel rail => Page
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.