Diesel Fuel Injection

Engine Control Modules (ECM) are equipped with On-Board Diagnostics (OBD). Always check DTC memory first, before performing repairs or troubleshooting. Vacuum hoses and connections should also be checked (false air).

For the electric components to work properly, a voltage of at least 11.5 V is required.

Do not use any silicone sealant. Traces of silicone components which are sucked into the engine are not burned there, and they damage the oxygen sensors.

The battery must only be disconnected and connected with the ignition switched off, since the Engine Control Modules (ECM) can otherwise be damaged.

Fuel hoses at engine must only be secured with spring-type clamps. The use of clamping collars or screw clamps is not permitted.

Vacuum hoses must not be clogged or kinked.

Spring clip installation tool VAS5024A is recommended for installing spring-type clips.

Fig 1: Identifying Spring Clamps VAS 5024A

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

Components marked with * are tested via On Board Diagnostic (OBD) DIAGNOSTIC MODE 03 - READ DTC MEMORY , Diagnostic mode 3: Check DTC memory.

It is possible that the control module will recognize a malfunction and store a DTC during some tests. Therefore the following work steps must be performed in the mentioned sequence after ending all tests and repairs.