Removal/refitting

The thermostat unit is installed on the rear side of the cylinder heads.

It ensures that the engine does not exceed the optimal temperature. Until the temperature of the coolant reaches 87 ± 2°C, the thermostat valve deviates the liquid directly to the pump: at temperatures above this value the opening of the thermostat valve conveys the liquid to the radiator.

The thermostat is provided with a sensor (NTC) which measures the temperature of the coolant and sends it to the Motronic control unit. Also present is an engine coolant temperature sender and a maximum temperature warning lamp contact connected to the instrument panel.

REMOVAL/REFITTING

• Remove the battery.

1. Disconnect the electrical connection from the engine coolant temperature sender and maximum temperature warning lamp contact.
2. Disconnect the electrical connection from the engine coolant temperature sensor (NTC).

1. Disconnect the electrical connection supplying the ignition coil
2. Unscrew the four screws and remove the coil without disconnecting it from the spark plug cables and place it on the engine.

• Drain the engine coolant system (see relative paragraph).

1. Remove sleeve connecting the radiator and ignition coil support.