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How Does a Bad Thermostat Affect Your BMW’s Performance?

The thermostat in your BMW plays a critical role in its performance. Although not very common, its failure can wreak havoc on its engine. To prevent any problems, a savvy driver needs to understand what a bad thermostat will do to their vehicle.

First, let’s understand how a thermostat regulates several of the processes in your car’s performance so it’s clear how its failure can damage your BMW.

BMW Bad Thermostat

The Engine Thermostat

The thermostat’s job is incredibly simple, and it is thus an incredibly simple piece of technology. The thermostat is a valve in your car’s cooling system which controls the flow of coolant to and from the radiator and around the cooling hoses.

By opening and closing the entrance of coolant into the cooling system, the thermostat regulates your car’s temperature, keeping it within a healthy range. The thermostat is therefore a crucial piece, as your BMW’s temperature needs to be in this range to function well and prevent future damage.

Signs of a Bad Thermostat

There are a few things that you may notice when a thermostat has gone bad, such as:

  • Overheating: It may come at no surprise that if the thermostat does not properly regulate the flow of coolant, your engine could be extremely overheated in no time. Overheating can seriously damage your engine if not addressed, so keep an eye on the temperature gauge. Overheating may be caused by several different issues, not just the thermostat, though.
  • Erratic Temperature Changes: Wide fluctuations in temperature is an indicator that something is wrong with your car’s cooling system. These changes, in which the temperature drops from extremely high to very low, are caused by improper influxes or restraints of coolant for the engine.
  • Coolant Leaks: If the thermostat is stuck closed, then coolant may build up and leak, often near the thermostat. This can cause other leaks to develop in coolant hoses.
  • Check Engine Light: The check engine light should always be taken seriously and never ignored. A bad thermostat will trigger this light in your BMW.

Ways a Bad Thermostat Affects Performance

A bad thermostat isn’t just bad for the cooling system, it’s bad for your car’s overall health and performance. Temperatures outside of the healthy range for your engine reduce your car’s efficiency. High temperatures can also decrease your car’s longevity if left untreated, or result in thousands of dollars of damage to critical engine parts, as they become misshapen and warped.

How can a thermostat fail?

There are three primary ways to think about thermostat failure. Thankfully, these don’t happen often as the thermostat is a pretty simple piece of technology and doesn’t wear much over time.

  • Stuck Closed: The thermostat, which is a valve that controls the flow of coolant to and from the radiator, may get stuck closed, typically due to issues with the wax and pistons in the valve. This is the worst way that the thermostat can fail; your car will overheat in a matter of minutes.
  • Stuck Open: On the flipside, the thermostat may also get stuck open. This is not as grave an issue as if it were stuck closed, as the coolant still readily flows through the cooling system, albeit too much. Your BMW may not reach its optimal temperature, particularly if it’s cold out, decreasing horsepower and fuel economy.
  • Stuck Halfway: The third way that a thermostat can fail is if it becomes stuck halfway, typically as a result of a jammed piston. This is much more common than being stuck open or closed, and is probably the least serious issue. While the engine may take longer to reach a good temperature, it also may slowly overheat during a long drive.

BMW Thermostat Replacement

The Best Garage to go for BMW Thermostat Issues

Fixing a bad thermostat is a difficult thing to do and should only be done if one is absolutely sure it is causing the problems you’re experiencing. This job is best left to BMW professionals, like Ultimate Bimmer Service.

Ultimate Bimmer Service is honored to serve the Carrolton and Dallas, Texas communities. Our customers are the most important thing to us, and giving you the best possible service is why we choose to focus only on BMW vehicles. Call us today to speak to any of our friendly staff members to set up your appointment.

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