Q: Coolant reservoir overflows while air conditioning is running

asked by on June 04, 2016

Car doesn't overheat but my coolant reservoir tank overflows while I have my a/c running. Why is this happening?

My car has 55000 miles.
My car has an automatic transmission.

Coolant is leaking Inspection $94.99 - $114.99 Get a Quote

Hello, A few different items can cause the coolant reservoir to overflow. If this is going on while the vehicle is not overheating, it is a bit less common.

The most likely causes would be a failure of one of these components:

When the AC is on, it puts a slight strain on the vehicle, which takes up some of the available horsepower.

A qualified Technician such as one from YourMechanic will be able to diagnose your coolant reservoir tank overflow fault and perform any repairs required.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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