Vauxhall Vectra car cuts out

Could you please tell me if its my airflow sensor thats causing the problem. Bought second hand sensor, worked for a wee while. I bought new air filter and put it in, it doesn't seem to work for long with new filter but when i take it out it runs fine or could it be plugs and leads. It has recently had work done, new timing belt, water pump, drive belt and exhaust manifold gasket.