Simon,
According to my Haynes Manual, "The canister purge solenoid valve is not opened by the ECU until the engine is fully warmed up and running under part load"
Not sure what EEC engine management version it is though. Ford EEC1V ??
When I did the Ford Engine management technician course way back in the annals of history-This was the course all the dealer techs were sent on
It was just as the Zetec had launched in the Escort with EECIV . We were taught then that the canister vented at cold start as extra enrichment and under full throttle conditions
