Lukis

Hi, So my opel desided not to start. First of all I thought the fuel's pump fuse went bad but sadly no, then I changed all of the spark plugs, fuel filter, checked the injections system everything works flawlessly. Changed the spark plugs and It started, went after an hour give or take It won't start agian. Maybe some of you had simalar problems and knows something what could of went bad? Realy need your help.