![E140/E150 [2006 - 2010]](/uploads/Toyota_Corolla_E140_2006_-_2010_.jpg)
Overheating of the Toyota Corolla engine
When the engine is running, a serviceable cooling system maintains optimal temperature conditions. Malfunctions in the cooling system can cause the engine to overheat. If you skip this moment, unpleasant consequences may arise: breakdown of the block head gasket, warpage of the head and, as a result, complex engine repairs.
There is a coolant temperature gauge in the left information display of the instrument panel. If the engine overheats, the pointer approaches the upper zone.
At the first signs of overheating, if the temperature gauge scale is completely shaded, but steam does not escape from under the hood, turn on the maximum interior heating mode (see "Heating, air conditioning and interior ventilation"). This is necessary in order to reduce the temperature of the coolant in the engine cooling system.
Turn on the hazard warning lights, depress the clutch pedal, then, using the vehicle's inertia, try to move carefully to the edge of the carriageway and stop as far to the right as possible at the side of the road, and if possible, outside the carriageway.
Let the engine run for a couple of minutes at normal engine speed and idling with the heater on at full power.
WARNING:
Do not stop the engine immediately! The only condition is to maintain the tightness of the cooling system. If a hose bursts or comes off, or if there is a leak other than fluid escaping from the expansion tank plug, the engine will have to be stopped immediately.
After stopping the overheated engine, local overheating of the coolant begins in the places of its contact with the most heat-stressed engine parts and the formation of steam locks. This phenomenon is called heatstroke.
Toyota Corolla Cooling System Check
1. Stop the engine.
2. Open the hood and inspect the engine compartment. Determine where the steam is coming from.
3. When inspecting the engine, pay attention to the presence of coolant in the expansion tank, to the intact rubber hoses, radiator and thermostat.
WARNING:
Never open the expansion tank cap directly. The liquid in the cooling system is under pressure . When you open the plug, the pressure will drop sharply, the liquid will boil, and its splashes can burn you. If you want to open the expansion tank cap on a hot engine, first put a thick, thick rag on top, and only then carefully turn the cap.
4. If a coolant leak is detected, the burst hose can be temporarily repaired with adhesive tape.
USEFUL ADVICE:
Reinforced (for example, silver colored) adhesive tape, which can be purchased at auto dealerships, is especially suitable for this purpose.
The leakage of a radiator, thermostat or heater is rather difficult to eliminate on the spot, therefore, in such a situation, it is necessary to add water to the cooling system, and when driving, carefully monitor the temperature indicator, periodically restoring the level in the cooling system.
WARNINGS:
Long-term use of water instead of antifreeze leads to the formation of scale in the engine cooling system, deterioration of its cooling and, as a consequence, to a reduction in the resource.
Never add cold water to an overheated engine. The engine must cool down with the hood open for at least 30 minutes.
5. The engine may overheat if the thermostat fails, which regulates the flow of fluid in the cooling system through or past the radiator (to speed up the warm-up of a cold engine). To check the thermostat, on a warm engine, check the temperature of the upper hose connecting the thermostat to the radiator by touch. If the upper radiator hose is cold, the thermostat is defective, there is no circulation through the radiator.
6. Very often the cause of motor overheating is the failure of the electric fan.
7. Start the engine. Monitor the temperature and note if the cooling fan comes on when the engine overheats. If it does not turn on, then the reasons may be a blown fuse, a malfunction of the fan turn-on relay, oxidized contacts in the wiring harness block, or a burned-out electric motor.
8. Replace the relay and fuse (see "Location of Fuses, Fuses and Relays and Their Replacement") in the fuse and relay mounting block installed in the engine compartment.
9. Replace the relay and fuse in the passenger compartment mounting block.
10. If, after replacing the relay and fuse, the fan does not start working, check the electric motor: take two additional wires and power it directly from the battery. The wires must be securely fastened and insulated.
WARNINGS:
Do not short-circuit the wires with each other! Pay attention to the polarity of the connection: the electric motor must rotate so that the fan blows air through the radiator to the motor. If the electric motor starts to work, the wiring or the relay for turning on the cooling fan is faulty; if not, the wiring or the actual motor is also faulty. Relay and motor are not repairable, replace them.
USEFUL TIPS:
There are two valves in the expansion tank plug: inlet and outlet. The exhaust valve plays an important role in ensuring optimal engine temperature. It maintains an excess pressure in the system of at least 0.13–0.15 MPa (1.3–1.5 kgf / cm2), providing an increase in the temperature of the beginning of boiling of the coolant and preventing intense vaporization.
When the valve is jammed in the closed position, with overheating, there is a significant excess of excess pressure - more than 0.15 MPa (1.5 kgf / cm2), which can lead to rupture of the expansion tank or breakdown of one of the hoses. In turn, valve jamming in the open position leads to premature boiling of the coolant. Therefore, once a year rinse the expansion tank plug with running water. If in doubt, replace the plug.
Obviously, if you remove the expansion tank plug on an overheated engine and this action coincides with a "thermal shock" in time, then liquid boiling and the formation of air jams in the cooling system will be guaranteed.
Every year, blow out the radiator cells with a jet of compressed air (for example, from a compressor), directing the jet first against the oncoming air flow, and then in its direction to remove dirt, adhering insects and road debris from the radiator surface. This will partially restore the efficiency of the radiator.
Source: http://toyotauto.net/corolla/proverka-sistemy-ohlazhdeniya.html
