MY MK5 ESCORT KEEPS CUTTING OUT?

I OWN A FORD 1993 MK5 ESCORT LX 1.6i 16V. WHEN DRIVING ALONG IT TRIES TO CUT OUT WHEN PUTTING THE CLUTCH IN AND SOMETIMES WILL JUST CUT OUT AND I HAVE TO PUT MY INDICATORS ON TO START IT AGAIN- IT WILL THEN GO FINE FOR A WHILE. EVEN WHEN DRIVING ALONG IT SHUDDERS AND TRIES TO CUT OUT. THE REVS GO FROM THE NORMAL 1000 REVS PER MIN TO 500 AND THEN IT CUTS OUT.

DOES ANYONE KNOW WHAT I CAN DO?. IT STARTED DOING THIS 2 WEEKS AGO BUT WAS FINE BEFORE THEN AS IT HAD A NEW MANIFOLD ETC... 2 MONTHS AGO

ANY INFO WILL BE GREAT

THANKS