Engine Cooling System Trouble in General: Inspection

WARNING: This page is about a different variant/trim than selected.

Trouble	Possible cause	Corrective action
Overheating	a. Engine coolant leaks, insufficient engine coolant	Check for coolant leaks, and repair or replace faulty parts if necessary. If no faulty parts are found, fill engine coolant.
	b. Clogged engine coolant passage	Clean or replace faulty parts.
	c. Defective radiator cap	Replace the radiator cap.
	d. Malfunction of thermostat	Replace the thermostat.
	e. Thermo control valve assembly malfunctioning	Replace the thermo-control valve assembly.
	f. Malfunction of water pump	Replace water pump.
	g. Clogged radiator fin	Clean the radiator fin. If it is not possible to clean, repair or replace the radiator.
	h. Radiator fan system malfunction	Check the radiator fan system, and repair or replace faulty parts.
	i. Excessive back pressure in exhaust system	Clean or replace faulty parts.
	j. Engine oil leaking into engine coolant	Repair or replace the faulty parts, clean the engine coolant passage, and then fill engine coolant.
Over cooling	a. Ambient temperature extremely low	Warm-up the engine sufficiently.
	b. Defective thermostat	Replace the thermostat.
	c. Thermo control valve assembly malfunctioning	Replace the thermo-control valve assembly.
Engine coolant leaks	a. Leakage from water pump	Replace water pump.
	b. Leakage from water hose	Repair or replace faulty parts.
	c. Leakage from water pipe	Repair or replace faulty parts.
	d. Leakage from cylinder head gasket	Replace the cylinder head gasket.
	e. Cracked or damaged cylinder head or cylinder block	Replace faulty parts.
	f. Cracked or damaged thermostat cover	Replace the thermostat cover.
	g. Leakage from thermo control valve assembly	Replace the thermo control valve assembly or gasket.
	h. Leakage from radiator	Repair or replace the radiator.
	i. Leakage from heater core	Replace the heater core.
Noise	a. Air mixed in the engine coolant passage	Bleed air from the engine coolant.
	b. Thermo control valve assembly malfunctioning	Replace the thermo-control valve assembly.
	c. Malfunction of water pump	Replace water pump.
	d. Malfunction of radiator fan or fan motor	Replace the radiator fan or fan motor.