INTRODUCTION - INTAKE AND EXHAUST MANIFOLDS

1.4 16v

INTAKE MANIFOLD

The intake manifold is equipped with a shuttering system for the inlet ducts incorporated in the connecting flange with the cylinder head.

The manifold consists of:

- a vacuum accumulator formed inside the manifold;

- a solenoid valve incorporated in the pneumatic control actuator;

- a slider valve;

- a slider valve position switch.

1. Slider valve plate

2. Slider valve position switch

3. Solenoid valve - pneumatic actuator (slider)

4. Control linkage

5. Vacuum reservoir

a. Slider valve plate travel

Operation

The injection control unit controls the two way solenoid valve which places the vacuum accumultor in contact with the pneumatic actuator which, by means of linkage, allows the sliding of a slider which shutters the flow of air through the two inlet ducts for each cylinder.

The sliding of the slider allows the following configurations:

- high swirl at low speeds and high recirculation of the exhaust gases where the slider valve plate closes the "neutral" inlet duct at each cylinder;

- full load and without exhaust gas recirculation, where the slider valve plate opens the two inlet ducts (neutral and tangential) at each cylinder.

Solenoid valve

This is a two-way solenoid built into the pneumatic actuator controlling the slider valve and it is controlled by the injection control unit.

Its function is to allow the vacuum present in the vacuum accumulator (inside the intake manifold) to act on the slider valve pneumatic actuator.

The solenoid valve-pneumatic actuator assembly and the valve position switch are incorporated in the intake manifold and therefore managed by the Parts Dept. as a single component.

1. Solenoid valve

2. Pneumatic actuator

3. Vacuum air pipe

4. Control linkage