Control Unit

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The control unit is located on left rear corner of engine compartment on Golf, Golf GT and Jetta models. On Vanagon, control unit may be located in trunk floor behind the rear seat or in the equipment box in cargo area. These units cannot be repaired. The control unit limits maximum engine speed to about 5500-5800 RPM. The control unit receives information from the following:

Air quantity from intake sensor.
Air temperature from temperature sensor (I).
Engine temperature from temperature sensor (II).
Exhaust oxygen content from O2 sensor.
Position of throttle valve from switch for full throttle enrichment.

The control unit uses this information to determine amount of fuel to be injected.