Which model Mondeo is it, what engine & gearbox, how old is it?

The early 57 / 58-registration Mondeo IV TDCIs (mostly 1.8 but some 2 litre models too) did have a problem with engine cut-out when decelerating for roundabouts / junctions. These problems were usually solved by an ECU update at the dealer.

It could be the idle control valve(if this car has one?)

This valve senses when the revs drop too low and increases the revs to prevent stalling.

The sensor can become dirty or faulty.

I'm sure someone will come along soon with where the sensor is?

Also have a look here...

http://www.talkford.com/topic/219626-engine-cutting-out-at-low-speed/

Edited by Videodoctor on 06/01/2014 at 22:41