i rolled my fiesta but had it repaired and now it wont stay running?

well i rolled my car a ford fiesta zetec s 52 plate i had it repaired and i start the car up but it doesn't stay running for long it seems like fuel starvation i've had checked by my mate from the AA and he says it's not showing any faults on his laptop anyone know what it could be it runs different amount of times i leave it turned off for about an hour it runs for about a minute or two then it struggles to stay running if i feather the throttle it will stay running but it then gradually cuts out i checked all the fuel lines and fuel filter and those seemed fine plenty of fuel coming out if anyone knows what it could be mostly appreciated:)