Starting problem on 2.0 petrol mondeo?

I have a 2 litre 2002 petrol Mondeo with a starting problem. Car engine turns over a number of times before eventually starting. Once engine is running the car drives perfectly. Problem isn't just related to cold starting given that after approximately 15 mins engine will prove difficult to start again. Been to Ford and had an engine diagnostic check. They claim that the inlet manifold gaskets needed replacing and would resolve problem. Given that Ford wanted to rip me off to the tune of £400 asked a competent mechanic to fit these but the problem still exists. Does anyone have any ideas?

Mark Burns
April 2008