PART A - Engine, Engine Management and Turbocharger

2. Electronic Engine Management - The Air System

The Air Cleaner

• The air cleaner has a replaceable filter cartridge which can easily be removed in service.

The Throttle Body

The throttle body (4) includes the throttle plate. The throttle plate setting screw (5) is factory set and sealed. It should not be altered in service. If the engine idle speed is not to specifications at the first servicing (1500 km), it can be adjusted by means of the basic idle speed control screw (see "Service Adjustments").

Bolted on to the throttle body are the idle speed control valve (.6) and the throttle position sensor (7). These are explained in the section covering "Sensors and Actuators",

The Air Chamber and Inlet Manifold

The throttle body is bolted on to the air chamber (3). Also fitted to the air chamber are

- the inlet air temperature sensor (11),
- the vacuum connector for the Manifold Absolute Pressure sensor (9),
- the vacuum connector for the fuel pressure regulator (10),
- the vacuum connector for the aircharge by-pass valve (13),
- and the vacuum connector for the crankcase ventilation filter (12) .

The air chamber is bolted on to the inlet manifold (2). The fuel rail with the plug-in fuel injectors (1) are fitted to the inlet manifold.

1 = Fuel rail with injectors
2 = Inlet manifold
3 = Air chamber
4 = Throttle body
5 = Throttle plate setting screw
6 = Basic idle speed control screw
7 = Throttle position sensor
8 = Idle speed control valve
9 = Connector - manifold absolute pressure sensor
10 = Connector - fuel pressure regulator
11 = Inlet air temperature sensor 12 = Connector - crankcase ventilation filter
13 = Connector - aircharge by-pass valve
14 = Connection - boost pressure gauge