1999 UK Focus 2.0 Saloon Ghia

In the last week the engine has been racing when I want to slow down and stalling when I stop. Driving me mad.

I end up coasting in neutral when coming to a stop with the enginer hitting 3000 revs. This continues until I actually stop when the car detects 0MPH it drops to 750 revs but then dips to 500 and tries to stall.

However just adding a bit of pressure to the accelerator does not work since the EMS fights me and I have to rev at approx 1500rpm to stop it stalling.

Any pointers to the fault gratefully received !