Removal and installation / inspection of K-Jetronic valve injectors (VW Passat B3)

Valve injectors inject fuel continuously before the intake valves. The amount of fuel injected is regulated by the fuel pressure. The valve injector injects fuel in a cone-shaped stream, and after the engine stops, it must close tightly. Leaky injectors cause difficulties when starting a hot engine. Injector defects sometimes lead to engine stalling, as well as to flashes in the engine after the ignition is turned off.

Removal the valve injectors / checking the jet shape and tightness

Remove the valve injectors from the intake manifold together with the fuel lines attached. The injectors are only inserted into the manifold and are easily removed.

Secure the nozzles in a suitable container.

The assistant should turn on the starter for a few seconds, while comparing the shape of the jets of the injectors with each other. The fuel should come out in a cone-shaped stream, the same for all the injectors.

Keep the starter on for about 10 seconds (the assistant does this), collect the fuel injected by the injectors.

Turn off the ignition.

Dry and examine the valve injectors at the nozzles. The injectors should not leak, otherwise replace the defective injector.

The workshop can check the performance of the injectors.

Install the injectors.

Caution: When reinstalling the injectors, make sure that the sealing rings are not damaged. Always replace the sealing rings. Moisten the sealing rings with fuel before installation.