Troubleshooting issues (Hyundai Elantra XD)

Sign	Probable cause	Method of elimination
Low compression in engine cylinders	The cylinder head gasket is blown	Replace the gasket
	Piston rings are worn or damaged	Replace the rings
	The piston or cylinder is worn out	Repair or replace piston and/or cylinder block
	The valve seat is worn or damaged	Repair or replace valve seat and/or valve
Low oil pressure	Low engine oil level	Check the engine oil level
	The oil pressure sensor is faulty	Replace the oil pressure sensor
	The oil filter is dirty	Replace the oil filter
	Oil pump gears or cover are worn out	Replace the oil pump or cover
	Liquid motor oil	Change engine oil
	The safety valve is open	Repair the safety valve
	Increased clearances in bearings	Replace the bearing shells
High oil pressure	The safety valve is closed	Repair the safety valve
Engine vibration	Engine mounts not tightened (front and back)	Tighten the engine mounts to the specified torque
	The gearbox mounting bracket is not tightened	Tighten the gearbox mounting bracket to the specified torque
	The subframe bracket is not tightened	Tighten the subframe bracket to the specified torque
	The central support is not tightened	Tighten the center support to the specified torque
	The gearbox support is damaged	Replace the gearbox mount
	The engine subframe support is damaged	Replace the subframe support
	The support shaft is damaged	Replace the support shaft
Valve noise	Liquid motor oil	Change engine oil
Valve noise	Worn or damaged valve stem or valve guide	Replace valves or valve guides
Knocking in the connecting rod or main bearings of the crankshaft	Insufficient oil supply	Check the engine oil level
	Liquid motor oil	Change engine oil
	Increased clearance in bearings	Replace the bearing shells
*Noise emitted by a toothed belt*	Incorrect timing belt tension	Adjust the timing belt tension
Low coolant level	Coolant Leak: Hoses Corroded or Cracked (radiator hose, heater hose, etc.)	Replace or tighten the clamps
	The radiator cap valve is faulty	Replace the radiator cap
	The thermostat housing is damaged	Replace the gasket or housing
	The radiator core is damaged	Replace
	The water pump or gasket is faulty	Replace the gasket or water pump
Contamination of radiator tubes	Foreign inclusions in the coolant	Replace the coolant
High coolant temperature	Thermostat is faulty	Replace Thermostat
	The radiator cap is faulty	Replace the radiator cap
	Clogged cooling system channels or hoses	Replace or clean clogged cooling system components
	The drive belt is loose or torn	Adjust tension or replace drive belt
	The water pump is faulty	Replace the water pump
	Coolant temperature sensor is faulty	Replace the coolant temperature sensor
	The electric radiator fan is faulty	Replace or repair the radiator fan
	The radiator temperature sensor is faulty	Replace the radiator temperature sensor
	Not enough coolant	Top up the coolant
Low coolant temperature	Thermostat is faulty	Replace Thermostat
Low coolant temperature	The coolant temperature sensor or its wiring is faulty	Replace the coolant temperature sensor
Electric radiator fan not working	The coolant temperature sensor, fan motor, radiator fan relay, electrical wiring, or fuse is defective	Replace or repair damaged components
Exhaust gas leaks	The connections are loose	Tighten the connections
Exhaust gas leaks	The pipe or muffler is damaged	Replace or repair the pipe or muffler
Extraneous noise from the exhaust system	The partition in the muffler is damaged	Replace the muffler
	The rubber support is damaged	Replace the rubber support
	The pipe or muffler is in contact with the body	Adjust the position of the exhaust system