Your vehicle's instrument cluster has a warning light for engine coolant overheating that comes on when the coolant temperature approaches a critical value.
Checking the cooling system
At the first sign of overheating, if the engine overheating warning light comes on, but there are no puffs of steam coming out from under the hood, turn on the maximum interior heating mode, see page 11. «Heating (conditioning) and 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 momentum, try to carefully move to the edge of the roadway and stop as far to the right as possible at the curb, and if possible, out of the roadway. Let the engine run for a couple of minutes at normal idle speed with the heater turned on at full power.
WARNING: If the cooling system is leaking (a hose has burst or jumped off, or another leak has formed, except for the ejection of fluid from under the plug of the expansion tank), the engine will have to be stopped immediately. In other cases, do not stop the engine immediately!
After the overheated engine stops, local overheating of the coolant begins at the points of its contact with the most heat-stressed engine parts and the formation of vapor locks. This phenomenon is called thermal shock.
1. Stop the engine.
2. Open the hood and inspect the engine compartment. Determine where the steam is coming from. When inspecting the engine, pay attention to the presence of coolant in the expansion tank, the integrity of the rubber hoses, radiator, thermostat.
WARNING: Never open the cap of the expansion tank immediately. The liquid in the cooling system is under pressure, when the plug is opened, the pressure will drop sharply, the liquid will boil, and its splashes can scald you. If you want to open the cap of the expansion tank on a hot engine, first put a thick thick rag on top and only then carefully turn the cap.
3. Look under the instrument panel - if there are any leaks or traces of coolant flowing from the heater radiator under it.
If a coolant leak is detected, the burst hose can be temporarily repaired with adhesive tape.
USEFUL ADVICE: Reinforced (e.g. silver) adhesive tape, which can be purchased at car dealerships.
A radiator, thermostat or heater leak is quite difficult to fix on the spot, so in such a situation it is necessary to add water to the cooling system and carefully monitor the temperature gauge while driving, 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 result, to a reduction in the resource.
Never add cold water to an overheated engine. It must cool down with the hood open for at least 30 minutes.
4. A broken or loose tension on the alternator and water pump drive belt almost always leads to engine overheating. If the belt breaks or the belt is worn to the point that the automatic tensioner does not maintain proper belt tension, replace the belt (see «Replacing accessory drive belts»).
5, The engine can overheat if the thermostat that controls the flow of fluid in the cooling system through or past the radiator fails (to accelerate the warm-up of a cold engine). To check the thermostat, on a warm engine, check the temperature of the hose connecting the thermostat to the radiator by touch. If the radiator hose is cold, the thermostat is bad and there is no circulation through the radiator.
6. Very often, the cause of overheating of the engine, the cooling system of which is equipped with an electric fan, is the failure of the fan. Start the engine, monitor the temperature and pay attention to whether the cooling fan turns on when the engine overheats.
7. If the fan does not turn on, check the integrity of the fuses No. 39 and 40 in the engine compartment mounting block, as well as the reliability of the fastening of the relays No. 53 and 61 of the radiator fan in the engine compartment mounting block.
8. If the fusible links are in good condition and the relays are inserted securely, remove the expansion tank (see «Removal and installation of a broad tank»,) and check the connection of the wiring harness block with the connector of the additional resistance of the electric fan.
9. If all checks fail, check the fan motor. To do this, disconnect the wiring harness connector from the additional resistance connector of the electric fan...
10.... then press the latch and disconnect the additional resistance from the fan casing.
11. Take the two extra wires and power the extra resistance leads directly from the battery. Wires must be securely fastened and insulated.
WARNING: Do not allow wires to short circuit with each other!
12. If the motor does not work, replace it (see «Removal and installation of the electric motor of the radiator fan of the engine cooling system and its additional resistance»). If the electric motor started to work, then it is working. In this case, check and repair the electrical circuit of the electric fan (see «Diagnostics of malfunctions of onboard electrical equipment»).
USEFUL ADVICE: Two valves are installed in the plug of the expansion tank - inlet and outlet. The exhaust valve plays a big role in ensuring optimum engine temperature. It maintains an excess pressure of at least 0.145 MPa in the system, providing an increase in the temperature at which the coolant begins to boil and preventing intense vaporization. Unfortunately, when the valve is stuck in the closed position during overheating, a significant excess of overpressure occurs - more than 0.15 MPa, which can lead to a rupture of the expansion tank or a breakdown of one of the hoses. In turn, the jamming of the valve in the open position leads to premature boiling of the coolant.
Therefore, once a year, rinse the plug of the expansion tank with running water. If in doubt, replace the plug. Obviously, if the plug of the expansion tank is removed on an overheated engine and this action coincides with thermal shock in time, then boiling of the liquid and the formation of air locks in the cooling system will be guaranteed.
Blow out the radiator cells with compressed air once a year (e.g. from a compressor), directing the jet first towards the oncoming air flow, and then in its direction to remove dirt, adhering insects and road debris from the surface of the radiator. So you can partially restore the efficiency of the radiator.