This listing is for Item Description Genuine OEM thermostat 87 degrees A1102000515 to suit W201, W124, W126 all with M102 Engine M103 Engine M104 Engine W116 M110 BRAND MAY VARY

A thermostat in a car is a device that maintains the engine's temperature within a specific range. It is located between the engine and the radiator and is a valve that opens or closes depending on the engine's temperature. The main function of a thermostat is to regulate the flow of coolant through the engine to maintain the desired temperature range. When the engine is cold, the thermostat remains closed, causing the coolant to circulate around the engine, allowing the engine to heat up quickly. Once the engine reaches its optimal temperature, the thermostat opens and allows the coolant to flow to the radiator. The coolant absorbs heat from the engine, dissipates it through the radiator, and returns to the engine to repeat the process.

The thermostat plays an essential role in protecting the engine from overheating, which can cause significant damage. If the engine's temperature rises above the safe range, the thermostat will trigger a warning light on the dashboard, indicating the driver to take necessary measures immediately. In addition, a malfunctioning thermostat can cause issues such as poor fuel economy, increased emissions, and sluggish acceleration. Therefore, it is crucial to ensure the thermostats are functioning correctly and replaced when necessary to keep the engine running smoothly and prolong its lifespan.