Oil level high
Air cleaner clogged
Fuel level in tank is high
High compression pressure
Defective starting motor
External fuel leak
Improper injection timing
Oil pressure high
Loose fan belt
Clogged fuel tank vent hole
Defective regulator
Battery full charge
Starter motor mounting bolt loose
Defective alternator
Defective thermostat valve
Clogged fuel filter
Defective pressure relief valve
Clogged silencer
Air in fuel system
Water in fuel system