ford escort 1990 petrol 1.4 lx keeps stalling when slowing down.
 

Car keeps stalling at junctions and have noticed on the carb that there is a wire missing from the side solenoid. Not sure what this solenoid is for, the car also smells of petrol and there is a rubbery smell. Have checked hoses for collapse but all seem to be okay.

Any ideas on what else to check and also what this solenoid is and where the wire goes?

Thank you.