Defective pressure relief valve assembly
Defective pressure gauge
Loose battery clamp
Clogged air cleaner
Worn out crank and cam shaft bearing
Defective injector
Weak compression
Defective battery
Piston ring wornout
Defective oil relief valve
Loose fan belt
Defective alternator
Improper valve timing
Excessive valve guide clearance
Clogged fuel filter
Defective pressure relief valve
Fuel filter clogged
Worn out liner