See also:

Ford Sierra Service Manual
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Specifications
Fuel evaporative emission control system - carburettor engines Ported vacuum switch operating temperature: Two-port valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

Carburettor (Ford VV type) - removal and refitting
Caution: Refer to the precautions in Section 1 before proceeding. Note: A new gasket must be used when refitting the carburettor. A tachometer and an exhaust gas analyser will be required to chec ...