Ignition system TFZ (Mercedes-Benz E-Class W124)

The TFZ ignition system works on the same principle as the EZL ignition system, but with the following differences.

In the TFZ ignition system, the ignition timing is determined by a sensor installed in the ignition distributor. This design makes it possible to set the initial ignition advance angle by turning the ignition distributor housing relative to the distributor shaft.

When the engine is running, the ignition advance angle is partly controlled by an electronic device and partly by a vacuum regulator mounted on the ignition distributor. The electronic control device increases the ignition advance angle with increasing engine speed, and the vacuum regulator - with increasing load.

On models with a carburetor, when the engine warms up, the thermal switch and control valve change the ignition timing via the vacuum correction unit.