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Frequently asked questions about cars and motorcycles

How the thermostat valve works in an engine

Model: (Various brands) Various
Part: Thermostat

Let’s see how a thermostat valve works: it is the only component capable of cooling the engine. As illustrated in the video, it allows the circulation of water in the engine, which heats up significantly during operation. The thermostat is set to 87°C, and when it reaches this temperature, it stops allowing water to flow into the engine and instead directs it to the radiator, which cools the water before it re-enters the engine. Without this valve, the engine would overheat beyond 90°C, the hoses would not withstand the temperature and would burst, causing water to leak from the radiator and the entire system, potentially leading to engine failure, and in severe cases, even a fire. As a precaution, it is recommended to replace the thermostat every 62,000 miles.

Updated on 1 July 2026 by ScegliAuto

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How to Reset the Central Locking of the Volkswagen Golf 4?

If the central locking system of the Volkswagen Golf 4 is not working, it is likely necessary to reset the system: to do this, open the driver's door and detach the side panel of the dashboard next to the steering wheel. Under this panel, you will find the fuses, including the one for the central locking, which is indicated in the manual as number 14. To reset the system, remove this fuse from its housing, then reinsert it or replace it with a new one of the same amperage: this will reset the central locking system.

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