Inlet air temperature system - general information and component renewal

Fuel system: multi-point injection models / Inlet air temperature system - general information and component renewal

General information
1 The inlet air regulation system consists of a temperature controlled vacuum switch, mounted in the air inlet ducting, a vacuum operated flap valve and several lengths of interconnecting vacuum hose. The switch senses the temperature of the inlet air and opens when a preset lower limit is reached. It then directs manifold vacuum to the flap valve which opens, allowing warm air drawn from around the exhaust manifold to blend with the inlet air.

Component renewal
Temperature switch
2 Remove the screw and detach the inlet air ducting from the top of the throttle body.

3 Disconnect the vacuum hoses from the temperature switch, noting their order of connection to ensure correct refitting (see illustration).

3.3 Disconnect the vacuum hoses from the temperature switch

4 Prise the metal retaining clip off the temperature switch ports, then press the switch body inside the ducting. Recover the gaskets (see illustration).

3.4 The temperature switch (arrowed) is located inside the throttle body inlet duct

5 Refitting is a reversal of removal.

Flap valve
6 The flap valve is removed with the air cleaner inlet ducting - remove the screw and detach the ducting from the front of the air cleaner.