Is his goal to get you fired? Time to dump that psycho. As to fuses, most of us aren't going to have a fuse diagram to look at so can't tell what fuse #8 is. But any fuse connected to the starting circuit could disable a vehicle from starting. Check against your diagram or in the manual what fuses are listed for each slot, and make sure a good fuse is in that place and has the correct rating (ie 10 amp, 15 amp, etc. Do not interchange these fuses. Make sure a 10 amp goes in the 10 amp slot, and so on.) You can buy a simple fuse kit in any parts store, it will contain a large variety of fuses and a tester. In addition to fuses there are relays that need to be in place for a vehicle to operate, such as a starter relay & fuel pump relay. These have 3 prongs and carry ratings from 30A to 50A. A quick way to keep a car from starting is to just pull the fuel pump relay. Good luck.