loss of power steering could be caused by the alternator dying if the pas pump is electronic (it is on astras so ford may be the same). if it is dying this could also cause the car to cut out at low revs as there may not be enough amps to power the fuel pump. get an electrical tester (multimeter) and test the voltage at the battery when the car is running and when the car is switched off. if the voltage is lower when the car is running its probably the alternator.
Joe, January 2010