MK6 2003 turning off engine when slowing and stopping

[SparkOfDeath]

My Fiesta Finesse 2003 MK6 is driving completely fine, but occasionally (In fact only on 2 occasions, today, and about a month ago) the car has a brief episode lasting about 15 minutes before returning to normal. 

In this time, the car will turn off the engine completely and make the steering very tough. This happens if I go into neutral and coast, if I drive too slow (The revs go too low), or I stop for a red light or go slow around a corner. After the 15 minutes or so are up, it returns to normal.

I've done my research and it seems that in most cars it's down to an idle control valve, but from what I can see on here, the MK6 doesn't have an idle control valve? I was hoping someone could elaborate for me..

I feel as if this is merely a matter of cleaning something rather than buying and replacing something. I'm quite clueless, but am eager to be pointed in the right direction.

Thanks in advance,

here's a photo of under my bonnet (The only photo I've got, taken after a crash a while back. It's all fixed now though)