How long does the coolant vacuum valve switch last?

The coolant vacuum valve switch opens when the heater is turned on and allows coolant from the engine to flow into the heater core. This warm air escaping from the engine provides warmth to the interior of the car. Air flows through the vents and can be controlled using switches next to the driver and passenger seats.

The vacuum part of the switch helps regulate the flow of air through the vents. Over time, the coolant vacuum valve switch can become clogged with old coolant or debris. If this happens, the derailleur may not work properly, meaning that you can be very uncomfortable driving if it is not replaced promptly.

The coolant vacuum valve switch has three parts. One is connected to the vacuum manifold, the second is connected to the vacuum carburetor, and the third is connected to the vacuum pressure on the distributor. As long as the engine is running at normal temperature, a vacuum of zero psi is created in the distributor. On hot days, when the engine temperature can rise very quickly, the switch switches the distributor from port vacuum to manifold vacuum. This increases timing and also increases engine RPM.

As soon as this happens, coolant flows through the engine and radiator, and the speed of the radiator fan increases. The engine temperature immediately drops to a safe level. Once the engine is at the right level, everything returns to normal until it starts to overheat or overcool again.

The switch can fail over time, so if this happens, have the coolant vacuum valve switch replaced by an experienced mechanic as soon as possible. You should also be aware of the symptoms a switch gives before it fails so you can be prepared and replace it before it fails completely.

Signs that the coolant vacuum valve sensor needs to be replaced include:

• Heat does not warm as it should
• Leakage of coolant inside the car or under the bottom of the car
• Cold air is blowing through the vents even if the knob indicates warm air is being supplied.

If you're experiencing any of the above issues, it might be time to get your car checked out. Make an appointment with a certified mechanic to diagnose and fix your problem.