I changed the cam belt bearing on my Fiesta 2003 1.6 Duratec this weekend, but after replacing all three belts, i've put all the bits back together and upon staring the engine, it starts fine, then looses revs and stalls the engine, the only way for the engine not to stall is to give it some gas, any ideas what might be the problem?

Sounds like the timing could be out. Did you use a locking kit?

I didnt have the official Ford timing kit at the time and just used a 30 mm screwdriver which was recommended by a friend of mine as thats how long the timing tool is..

The official kit will also have a bar for the camshafts as well as the crankshaft pin.

OK Thanks, do you think this will sort out the overall timing of the engine and stablise the engine when ticking over? I'm hoping to do this tomorrow

The engine is stalling as the timing is out enough to mean that the valves are out of phase with the piston stroke.

Hopefully it's only a tooth or two out or major top end damage will occur.