Thermostat vital part of engine's cooling system

The thermostat is a simple component of a vehicle's cooling system, which performs a major job essential to its performance.

A basic thermostat consists of an outer body that houses a temperature-sensitive valve that opens and closes based solely on coolant temperature. Most thermostats operate completely off coolant temperature. However, some cars use computer-controlled thermostats that are controlled by what is known as the powertrain control module or PCM.

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In most vehicles the thermostat is located toward the top of the engine, inside the outlet going to the radiator. In some cases, the thermostat may be mounted toward the bottom of the engine near the inlet to the engine. Thermostats have a rating in degrees that reflects the typical cooling system temperature maintained by the thermostat.

How does this regulator work, you ask?

The thermostat is a valve that either restricts or allows the flow of coolant from the engine to the radiator. When the engine is cold the thermostat stays shut confining the coolant to the engine only. The purpose of this is to help the coolant to warm up. As the coolant warms, the valve in the thermostat begins to open, allowing the coolant to now flow to the radiator and back to the engine. During normal conditions with a fully warmed engine, the thermostat will allow an unrestricted flow of coolant to the radiator.

What happens if this part becomes defective? A bad thermostat can lead to issues such as overheating, low heater output, knocking or pinging when accelerating, poor fuel economy, high idle speed, an electric cooling fan that runs continuously, and abnormally low-temperature gauge readings. These problems will not only cause problems for your wallet but could also leave you stranded on the side of the road in the hot sun.

To avoid experiencing one of these issues first-hand, visit www.geminicarcare.com to find a quality local auto-repair center to check the condition of your thermostat.